Plug the new PG combinator into monitor

docs/config/monitor.en.md

@@ -15,6 +15,7 @@ These parameters only apply to Monitors.
 - [mon_stats_timeout](#mon_stats_timeout)
 - [osd_out_time](#osd_out_time)
 - [placement_levels](#placement_levels)
+- [use_old_pg_combinator](#use_old_pg_combinator)
 
 ## etcd_mon_ttl
 
@@ -77,3 +78,11 @@ values.  Smaller priority means higher level in tree. For example,
 levels are always predefined and can't be removed. If one of them is not
 present in the configuration, then it is defined with the default priority
 (100 for "host", 101 for "osd").
+
+## use_old_pg_combinator
+
+- Type: boolean
+- Default: false
+
+Use the old PG combination generator which doesn't support [level_placement](pool.en.md#level_placement)
+and [raw_placement](pool.en.md#raw_placement) for pools which don't use this features.

docs/config/monitor.ru.md

@@ -15,6 +15,7 @@
 - [mon_stats_timeout](#mon_stats_timeout)
 - [osd_out_time](#osd_out_time)
 - [placement_levels](#placement_levels)
+- [use_old_pg_combinator](#use_old_pg_combinator)
 
 ## etcd_mon_ttl
 
@@ -78,3 +79,11 @@ OSD перед обновлением агрегированной статис
 "host" и "osd" являются предопределёнными и не могут быть удалены. Если
 один из них отсутствует в конфигурации, он доопределяется с приоритетом по
 умолчанию (100 для уровня "host", 101 для "osd").
+
+## use_old_pg_combinator
+
+- Тип: булево (да/нет)
+- Значение по умолчанию: false
+
+Использовать старый генератор комбинаций PG, не поддерживающий [level_placement](pool.ru.md#level_placement)
+и [raw_placement](pool.ru.md#raw_placement) для пулов, которые не используют данные функции.

docs/config/pool.en.md

@@ -32,6 +32,8 @@ Parameters:
 - [pg_minsize](#pg_minsize)
 - [pg_count](#pg_count)
 - [failure_domain](#failure_domain)
+- [level_placement](#level_placement)
+- [raw_placement](#raw_placement)
 - [max_osd_combinations](#max_osd_combinations)
 - [block_size](#block_size)
 - [bitmap_granularity](#bitmap_granularity)
@@ -209,6 +211,69 @@ never put on OSDs in the same failure domain (for example, on the same host).
 So failure domain specifies the unit which failure you are protecting yourself
 from.
 
+## level_placement
+
+- Type: string
+
+Additional failure domain rules, applied in conjuction with failure_domain.
+Must be specified in the following form:
+
+`<placement level>=<sequence of characters>, <level2>=<sequence2>, ...`
+
+Sequence should be exactly [pg_size](#pg_size) character long. Each character
+corresponds to an OSD in the PG of this pool. Equal characters mean that
+corresponding items of the PG should be placed into the same placement tree
+item at this level. Different characters mean that items should be placed into
+different items.
+
+For example, if you want a EC 4+2 pool and you want every 2 chunks to be stored
+in its own datacenter and you also want each chunk to be stored on a different
+host, you should set `level_placement` to `dc=112233 host=123456`.
+
+Or you can set `level_placement` to `dc=112233` and leave `failure_domain` empty,
+because `host` is the default `failure_domain` and it will be applied anyway.
+
+Without this rule, it may happen that 3 chunks will be stored on OSDs in the
+same datacenter, and the data will become inaccessibly if that datacenter goes
+down in this case.
+
+Of course, you should group your hosts into datacenters before applying the rule
+by setting [placement_levels](monitor.en.md#placement_levels) to something like
+`{"dc":90,"host":100,"osd":110}` and add DCs to [node_placement](#placement-tree),
+like `{"dc1":{"level":"dc"},"host1":{"parent":"dc1"},...}`.
+
+## raw_placement
+
+- Type: string
+
+Raw PG placement rules, specified in the form of a DSL (domain-specific language).
+Use only if you really know what you're doing :)
+
+DSL specification:
+
+```
+dsl := item | item ("\n" | ",") items
+item := "any" | rules
+rules := rule | rule rules
+rule := level operator arg
+level := /\w+/
+operator := "!=" | "=" | ">" | "?="
+arg := value | "(" values ")"
+values := value | value "," values
+value := item_ref | constant_id
+item_ref := /\d+/
+constant_id := /"([^"]+)"/
+```
+
+"?=" operator means "preferred". I.e. `dc ?= "meow"` means "prefer datacenter meow
+for this chunk, but put into another dc if it's unavailable".
+
+Examples:
+
+- Simple 3 replicas with failure_domain=host: `any, host!=1, host!=(1,2)`
+- EC 4+2 in 3 DC: `any, dc=1 host!=1, dc!=1, dc=3 host!=3, dc!=(1,3), dc=5 host!=5`
+- 1 replica in fixed DC + 2 in random DCs: `dc?=meow, dc!=1, dc!=(1,2)`
+
 ## max_osd_combinations
 
 - Type: integer

docs/config/pool.ru.md

@@ -31,6 +31,8 @@
 - [pg_minsize](#pg_minsize)
 - [pg_count](#pg_count)
 - [failure_domain](#failure_domain)
+- [level_placement](#level_placement)
+- [raw_placement](#raw_placement)
 - [max_osd_combinations](#max_osd_combinations)
 - [block_size](#block_size)
 - [bitmap_granularity](#bitmap_granularity)
@@ -161,7 +163,7 @@ OSD, PG деактивируется на чтение и запись. Иным
 Для примера, разница между pg_minsize 2 и 1 в реплицированном пуле с 3 копиями
 данных (pg_size=3), проявляется следующим образом:
 - Если 2 сервера отключаются при pg_minsize=2, пул становится неактивным и
-  остаётся неактивным в течение [osd_out_time](monitor.en.md#osd_out_time)
+  остаётся неактивным в течение [osd_out_time](monitor.ru.md#osd_out_time)
   (10 минут), после чего монитор назначает другие OSD/серверы на замену, пул
   поднимается и начинает восстанавливать недостающие копии данных. Соответственно,
   если OSD на замену нет - то есть, если у вас всего 3 сервера с OSD и 2 из них
@@ -169,7 +171,7 @@ OSD, PG деактивируется на чтение и запись. Иным
   или не добавите хотя бы 1 сервер (или не переключите failure_domain на "osd").
 - Если 2 сервера отключаются при pg_minsize=1, ввод-вывод лишь приостанавливается
   на короткое время, до тех пор, пока монитор не поймёт, что OSD отключены
-  (что занимает 5-10 секунд при стандартном [etcd_report_interval](osd.en.md#etcd_report_interval)).
+  (что занимает 5-10 секунд при стандартном [etcd_report_interval](osd.ru.md#etcd_report_interval)).
   После этого ввод-вывод восстанавливается, но новые данные временно пишутся
   всего в 1 копии. Когда же проходит osd_out_time, монитор точно так же назначает
   другие OSD на замену выбывшим и пул начинает восстанавливать копии данных.
@@ -211,6 +213,71 @@ PG в Vitastor эферемерны, то есть вы можете менят
 Иными словами, домен отказа - это то, от отказа чего вы защищаете себя избыточным
 хранением.
 
+## level_placement
+
+- Тип: строка
+
+Правила дополнительных доменов отказа, применяемые вместе с failure_domain.
+Должны задаваться в следующем виде:
+
+`<уровень>=<последовательность символов>, <уровень2>=<последовательность2>, ...`
+
+Каждая `<последовательность>` должна состоять ровно из [pg_size](#pg_size) символов.
+Каждый символ соответствует одному OSD (размещению одной части PG) этого пула.
+Одинаковые символы означают, что соответствующие части размещаются в один и тот же
+узел дерева OSD на заданном `<уровне>`. Разные символы означают, что части
+размещаются в разные узлы.
+
+Например, если вы хотите сделать пул EC 4+2 и хотите поместить каждые 2 части
+данных в свой датацентр, и также вы хотите, чтобы каждая часть размещалась на
+другом хосте, то вы должны задать `level_placement` равным `dc=112233 host=123456`.
+
+Либо вы просто можете задать `level_placement` равным `dc=112233` и оставить
+`failure_domain` пустым, т.к. `host` это его значение по умолчанию и оно также
+применится автоматически.
+
+Без этого правила может получиться так, что в одном из датацентров окажется
+3 части данных одной PG и данные окажутся недоступными при временном отключении
+этого датацентра.
+
+Естественно, перед установкой правила вам нужно сгруппировать ваши хосты в
+датацентры, установив [placement_levels](monitor.ru.md#placement_levels) во что-то
+типа `{"dc":90,"host":100,"osd":110}` и добавив датацентры в [node_placement](#дерево-размещения),
+примерно так: `{"dc1":{"level":"dc"},"host1":{"parent":"dc1"},...}`.
+
+## raw_placement
+
+- Type: string
+
+Низкоуровневые правила генерации PG в форме DSL (доменно-специфичного языка).
+Используйте, только если действительно знаете, зачем вам это надо :)
+
+Спецификация DSL:
+
+```
+dsl := item | item ("\n" | ",") items
+item := "any" | rules
+rules := rule | rule rules
+rule := level operator arg
+level := /\w+/
+operator := "!=" | "=" | ">" | "?="
+arg := value | "(" values ")"
+values := value | value "," values
+value := item_ref | constant_id
+item_ref := /\d+/
+constant_id := /"([^"]+)"/
+```
+
+Оператор "?=" означает "предпочитаемый". Т.е. `dc ?= "meow"` означает "предпочитать
+датацентр meow для этой части данных, но разместить её в другом датацентре, если
+meow недоступен".
+
+Примеры:
+
+- Простые 3 реплики с failure_domain=host: `any, host!=1, host!=(1,2)`
+- EC 4+2 в 3 датацентрах: `any, dc=1 host!=1, dc!=1, dc=3 host!=3, dc!=(1,3), dc=5 host!=5`
+- 1 копия в фиксированном ДЦ + 2 в других ДЦ: `dc?=meow, dc!=1, dc!=(1,2)`
+
 ## max_osd_combinations
 
 - Тип: целое число

docs/config/src/monitor.yml

@@ -63,3 +63,12 @@
     "host" и "osd" являются предопределёнными и не могут быть удалены. Если
     один из них отсутствует в конфигурации, он доопределяется с приоритетом по
     умолчанию (100 для уровня "host", 101 для "osd").
+- name: use_old_pg_combinator
+  type: bool
+  default: false
+  info: |
+    Use the old PG combination generator which doesn't support [level_placement](pool.en.md#level_placement)
+    and [raw_placement](pool.en.md#raw_placement) for pools which don't use this features.
+  info_ru: |
+    Использовать старый генератор комбинаций PG, не поддерживающий [level_placement](pool.ru.md#level_placement)
+    и [raw_placement](pool.ru.md#raw_placement) для пулов, которые не используют данные функции.

docs/usage/cli.en.md

@@ -269,6 +269,8 @@ Optional parameters:
 | `--block_size 128k`            | Put pool only on OSDs with this data block size                            |
 | `--bitmap_granularity 4k`      | Put pool only on OSDs with this logical sector size                        |
 | `--immediate_commit none`      | Put pool only on OSDs with this or larger immediate_commit (none < small < all) |
+| `--level_placement <rules>`    | Use additional failure domain rules (example: "dc=112233")                 |
+| `--raw_placement <rules>`      | Specify raw PG generation rules ([details](../config/pool.en.md#raw_placement)) |
 | `--primary_affinity_tags tags` | Prefer to put primary copies on OSDs with all specified tags               |
 | `--scrub_interval <time>`      | Enable regular scrubbing for this pool. Format: number + unit s/m/h/d/M/y  |
 | `--used_for_fs <name>`         | Mark pool as used for VitastorFS with metadata in image <name>             |

docs/usage/cli.ru.md

@@ -286,6 +286,8 @@ vitastor-cli snap-create [-p|--pool <id|name>] <image>@<snapshot>
 | `--block_size 128k`            | ...только OSD с данным размером блока                                      |
 | `--bitmap_granularity 4k`      | ...только OSD с данным размером логического сектора                        |
 | `--immediate_commit none`      | ...только OSD с этим или большим immediate_commit (none < small < all)     |
+| `--level_placement <rules>`    | Задать правила дополнительных доменов отказа (пример: "dc=112233")         |
+| `--raw_placement <rules>`      | Задать низкоуровневые правила генерации PG ([детали](../config/pool.ru.md#raw_placement)) |
 | `--primary_affinity_tags tags` | Предпочитать OSD со всеми данными тегами для роли первичных                |
 | `--scrub_interval <time>`      | Включить скрабы с заданным интервалом времени (число + единица s/m/h/d/M/y) |
 | `--pg_stripe_size <number>`    | Увеличить блок группировки объектов по PG                                  |

mon/dsl_pgs.js

@@ -0,0 +1,408 @@
+const { select_murmur3 } = require('./murmur3.js');
+
+const NO_OSD = 'Z';
+
+class RuleCombinator
+{
+    constructor(osd_tree, rules, max_combinations, ordered)
+    {
+        this.osd_tree = index_tree(Object.values(osd_tree).filter(o => o.id));
+        this.rules = rules;
+        this.max_combinations = max_combinations;
+        this.ordered = ordered;
+    }
+
+    random_combinations()
+    {
+        return random_custom_combinations(this.osd_tree, this.rules, this.max_combinations, this.ordered);
+    }
+
+    check_combinations(pgs)
+    {
+        return check_custom_combinations(this.osd_tree, this.rules, pgs);
+    }
+}
+
+// Convert alternative "level-index" format to rules
+// level_index = { [level: string]: string | string[] }
+// level_sequence = optional, levels from upper to lower, i.e. [ 'dc', 'host' ]
+// Example: level_index = { dc: "112233", host: "ABCDEF" }
+function parse_level_indexes(level_index, level_sequence)
+{
+    const rules = [];
+    const lvl_first = {};
+    for (const level in level_index)
+    {
+        const idx = level_index[level];
+        while (rules.length < idx.length)
+        {
+            rules.push([]);
+        }
+        const seen = {};
+        for (let i = 0; i < idx.length; i++)
+        {
+            if (!seen[idx[i]])
+            {
+                const other = Object.values(seen);
+                if (other.length)
+                {
+                    rules[i].push([ level, '!=', other ]);
+                }
+                seen[idx[i]] = i+1;
+            }
+            else
+            {
+                rules[i].push([ level, '=', seen[idx[i]] ]);
+            }
+        }
+        lvl_first[level] = seen;
+    }
+    if (level_sequence)
+    {
+        // Prune useless rules for the sake of prettiness
+        // For simplicity, call "upper" level DC and "lower" level host
+        const level_prio = Object.keys(level_sequence).reduce((a, c) => { a[level_sequence[c]] = c; return a; }, {});
+        for (let upper_i = 0; upper_i < level_sequence.length-1; upper_i++)
+        {
+            const upper_level = level_sequence[upper_i];
+            for (let i = 0; i < rules.length; i++)
+            {
+                const noteq = {};
+                for (let k = 0; k < level_index[upper_level].length; k++)
+                {
+                    // If upper_level[x] is different from upper_level[y]
+                    // then lower_level[x] is also different from lower_level[y]
+                    if (level_index[upper_level][k] != level_index[upper_level][i])
+                    {
+                        noteq[k+1] = true;
+                    }
+                }
+                for (let j = 0; j < rules[i].length; j++)
+                {
+                    if (level_prio[rules[i][j][0]] != null && level_prio[rules[i][j][0]] > upper_i && rules[i][j][1] == '!=')
+                    {
+                        rules[i][j][2] = rules[i][j][2].filter(other_host => !noteq[other_host]);
+                        if (!rules[i][j][2].length)
+                        {
+                            rules[i].splice(j--, 1);
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return rules;
+}
+
+// Parse rules in DSL format
+// dsl := item | item ("\n" | ",") items
+// item := "any" | rules
+// rules := rule | rule rules
+// rule := level operator arg
+// level := /\w+/
+// operator := "!=" | "=" | ">" | "?="
+// arg := value | "(" values ")"
+// values := value | value "," values
+// value := item_ref | constant_id
+// item_ref := /\d+/
+// constant_id := /"([^"]+)"/
+//
+// Output: [ level, operator, value ][][]
+function parse_pg_dsl(text)
+{
+    const tokens = [ ...text.matchAll(/\w+|!=|\?=|[>=\(\),\n]|"([^\"]+)"/g) ].map(t => [ t[0], t.index ]);
+    let positions = [ [] ];
+    let rules = positions[0];
+    for (let i = 0; i < tokens.length; )
+    {
+        if (tokens[i][0] === '\n' || tokens[i][0] === ',')
+        {
+            rules = [];
+            positions.push(rules);
+            i++;
+        }
+        else if (!rules.length && tokens[i][0] === 'any' && (i == tokens.length-1 || tokens[i+1][0] === ',' || tokens[i+1][0] === '\n'))
+        {
+            i++;
+        }
+        else
+        {
+            if (!/^\w/.exec(tokens[i][0]))
+            {
+                throw new Error('Unexpected '+tokens[i][0]+' at '+tokens[i][1]+' (level name expected)');
+            }
+            if (i > tokens.length-3)
+            {
+                throw new Error('Unexpected EOF (operator and value expected)');
+            }
+            if (/^\w/.exec(tokens[i+1][0]) || tokens[i+1][0] === ',' || tokens[i+1][0] === '\n')
+            {
+                throw new Error('Unexpected '+tokens[i+1][0]+' at '+tokens[i+1][1]+' (operator expected)');
+            }
+            if (!/^[\w"(]/.exec(tokens[i+2][0])) // "
+            {
+                throw new Error('Unexpected '+tokens[i+2][0]+' at '+tokens[i+2][1]+' (id, round brace, number or node ID expected)');
+            }
+            let rule = [ tokens[i][0], tokens[i+1][0], tokens[i+2][0] ];
+            i += 3;
+            if (rule[2][0] == '"')
+            {
+                rule[2] = { id: rule[2].substr(1, rule[2].length-2) };
+            }
+            else if (rule[2] === '(')
+            {
+                rule[2] = [];
+                while (true)
+                {
+                    if (i > tokens.length-1)
+                    {
+                        throw new Error('Unexpected EOF (expected list and a closing round brace)');
+                    }
+                    if (tokens[i][0] === ',')
+                    {
+                        i++;
+                    }
+                    else if (tokens[i][0] === ')')
+                    {
+                        i++;
+                        break;
+                    }
+                    else if (tokens[i][0][0] === '"')
+                    {
+                        rule[2].push({ id: tokens[i][0].substr(1, tokens[i][0].length-2) });
+                        i++;
+                    }
+                    else if (/^\d+$/.exec(tokens[i][0]))
+                    {
+                        const n = 0|tokens[i][0];
+                        if (!n)
+                        {
+                            throw new Error('Level reference cannot be 0 (refs count from 1) at '+tokens[i][1]);
+                        }
+                        else if (n > positions.length)
+                        {
+                            throw new Error('Forward references are forbidden at '+tokens[i][1]);
+                        }
+                        rule[2].push(n);
+                        i++;
+                    }
+                    else if (!/^\w/.exec(tokens[i][0]))
+                    {
+                        throw new Error('Unexpected '+tokens[i][0]+' at '+tokens[i][1]+' (number or node ID expected)');
+                    }
+                    else
+                    {
+                        rule[2].push({ id: tokens[i][0] });
+                        i++;
+                    }
+                }
+            }
+            else if (!/^\d+$/.exec(rule[2]))
+            {
+                rule[2] = { id: rule[2] };
+            }
+            else
+            {
+                rule[2] = 0|rule[2];
+                if (!rule[2])
+                {
+                    throw new Error('Level reference cannot be 0 (refs count from 1) at '+tokens[i-1][1]);
+                }
+                else if (rule[2] > positions.length)
+                {
+                    throw new Error('Forward references are forbidden at '+tokens[i-1][1]);
+                }
+            }
+            rules.push(rule);
+        }
+    }
+    return positions;
+}
+
+// osd_tree = index_tree() output
+// levels = { string: number }
+// rules = [ level, operator, value ][][]
+//   level = string
+//   operator = '=' | '!=' | '>' | '?='
+//   value = number|number[] | { id: string|string[] }
+// examples:
+// 1) simple 3 replicas with failure_domain=host:
+//    [ [], [ [ 'host', '!=', 1 ] ], [ [ 'host', '!=', [ 1, 2 ] ] ] ]
+//    in DSL form: any, host!=1, host!=(1,2)
+// 2) EC 4+2 in 3 DC:
+//    [ [], [ [ 'dc', '=', 1 ], [ 'host', '!=', 1 ] ],
+//      [ 'dc', '!=', 1 ], [ [ 'dc', '=', 3 ], [ 'host', '!=', 3 ] ],
+//      [ 'dc', '!=', [ 1, 3 ] ], [ [ 'dc', '=', 5 ], [ 'host', '!=', 5 ] ] ]
+//    in DSL form: any, dc=1 host!=1, dc!=1, dc=3 host!=3, dc!=(1,3), dc=5 host!=5
+// 3) 1 replica in fixed DC + 2 in random DCs:
+//    [ [ [ 'dc', '=', { id: 'meow' } ] ], [ [ 'dc', '!=', 1 ] ], [ [ 'dc', '!=', [ 1, 2 ] ] ] ]
+//    in DSL form: dc=meow, dc!=1, dc!=(1,2)
+// 4) 2 replicas in each DC (almost the same as (2)):
+//    DSL: any, dc=1 host!=1, dc!=1, dc=3 host!=3
+// Alternative simpler way to specify rules would be: [ DC: 112233 HOST: 123456 ]
+function random_custom_combinations(osd_tree, rules, count, ordered)
+{
+    const r = {};
+    const first = filter_tree_by_rules(osd_tree, rules[0], []);
+    let max_size = 0;
+    // All combinations for the first item (usually "any") to try to include each OSD at least once
+    for (const f of first)
+    {
+        const selected = [ f ];
+        for (let i = 1; i < rules.length; i++)
+        {
+            const filtered = filter_tree_by_rules(osd_tree, rules[i], selected);
+            const idx = select_murmur3(filtered.length, i => 'p:'+f.id+':'+filtered[i].id);
+            selected.push(idx == null ? { levels: {}, id: null } : filtered[idx]);
+        }
+        const size = selected.filter(s => s.id !== null).length;
+        max_size = max_size < size ? size : max_size;
+        const pg = selected.map(s => s.id === null ? NO_OSD : (0|s.id));
+        if (!ordered)
+            pg.sort();
+        r['pg_'+pg.join('_')] = pg;
+    }
+    // Pseudo-random selection
+    for (let n = 0; n < count; n++)
+    {
+        const selected = [];
+        for (const item_rules of rules)
+        {
+            const filtered = selected.length ? filter_tree_by_rules(osd_tree, item_rules, selected) : first;
+            const idx = select_murmur3(filtered.length, i => n+':'+filtered[i].id);
+            selected.push(idx == null ? { levels: {}, id: null } : filtered[idx]);
+        }
+        const size = selected.filter(s => s.id !== null).length;
+        max_size = max_size < size ? size : max_size;
+        const pg = selected.map(s => s.id === null ? NO_OSD : (0|s.id));
+        if (!ordered)
+            pg.sort();
+        r['pg_'+pg.join('_')] = pg;
+    }
+    // Exclude PGs with less successful selections than maximum
+    for (const k in r)
+    {
+        if (r[k].filter(s => s !== NO_OSD).length < max_size)
+        {
+            delete r[k];
+        }
+    }
+    return r;
+}
+
+function filter_tree_by_rules(osd_tree, rules, selected)
+{
+    let cur = osd_tree[''].children;
+    for (const rule of rules)
+    {
+        const val = (rule[2] instanceof Array ? rule[2] : [ rule[2] ])
+            .map(v => v instanceof Object ? v.id : selected[v-1].levels[rule[0]]);
+        let preferred = [], other = [];
+        for (let i = 0; i < cur.length; i++)
+        {
+            const item = cur[i];
+            const level_id = item.levels[rule[0]];
+            if (level_id)
+            {
+                if (rule[1] == '>' && val.filter(v => level_id <= v).length == 0 ||
+                    (rule[1] == '=' || rule[1] == '?=') && val.filter(v => level_id != v).length == 0 ||
+                    rule[1] == '!=' && val.filter(v => level_id == v).length == 0)
+                {
+                    // Include
+                    preferred.push(item);
+                }
+                else if (rule[1] == '?=' && val.filter(v => level_id != v).length > 0)
+                {
+                    // Non-preferred
+                    other.push(item);
+                }
+            }
+            else if (item.children)
+            {
+                // Descend
+                cur.splice(i+1, 0, ...item.children);
+            }
+        }
+        cur = preferred.length ? preferred : other;
+    }
+    // Get leaf items
+    for (let i = 0; i < cur.length; i++)
+    {
+        if (cur[i].children)
+        {
+            // Descend
+            cur.splice(i, 1, ...cur[i].children);
+            i--;
+        }
+    }
+    return cur;
+}
+
+// Convert from
+// node_list = { id: string|number, level: string, size?: number, parent?: string|number }[]
+// to
+// node_tree = { [node_id]: { id, level, size?, parent?, children?: child_node_id[], levels: { [level]: id, ... } } }
+function index_tree(node_list)
+{
+    const tree = { '': { children: [], levels: {} } };
+    for (const node of node_list)
+    {
+        tree[node.id] = { ...node, levels: {} };
+        delete tree[node.id].children;
+    }
+    for (const node of node_list)
+    {
+        const parent_id = node.parent && tree[node.parent] ? node.parent : '';
+        tree[parent_id].children = tree[parent_id].children || [];
+        tree[parent_id].children.push(tree[node.id]);
+    }
+    const cur = tree[''].children;
+    for (let i = 0; i < cur.length; i++)
+    {
+        cur[i].levels[cur[i].level] = cur[i].id;
+        if (cur[i].children)
+        {
+            for (const child of cur[i].children)
+            {
+                child.levels = { ...cur[i].levels, ...child.levels };
+            }
+            cur.splice(i, 1, ...cur[i].children);
+            i--;
+        }
+    }
+    return tree;
+}
+
+// selection = id[]
+// osd_tree = index_tree output
+// rules = parse_pg_dsl output
+function check_custom_combinations(osd_tree, rules, pgs)
+{
+    const res = [];
+    skip_pg: for (const pg of pgs)
+    {
+        let selected = pg.map(id => osd_tree[id] || null);
+        for (let i = 0; i < rules.length; i++)
+        {
+            const filtered = filter_tree_by_rules(osd_tree, rules[i], selected);
+            if (selected[i] === null && filtered.length ||
+                !filtered.filter(ok => selected[i].id === ok.id).length)
+            {
+                continue skip_pg;
+            }
+        }
+        res.push(pg);
+    }
+    return res;
+}
+
+module.exports = {
+    RuleCombinator,
+    NO_OSD,
+
+    index_tree,
+    parse_level_indexes,
+    parse_pg_dsl,
+    random_custom_combinations,
+    check_custom_combinations,
+};

mon/lp-optimizer.js

@@ -50,15 +50,15 @@ async function lp_solve(text)
     return { score, vars };
 }
 
-async function optimize_initial({ osd_tree, pg_count, pg_size = 3, pg_minsize = 2, max_combinations = 10000, parity_space = 1, ordered = false })
+// osd_weights = { [id]: weight }
+async function optimize_initial({ osd_weights, combinator, pg_count, pg_size = 3, pg_minsize = 2, parity_space = 1, ordered = false })
 {
-    if (!pg_count || !osd_tree)
+    if (!pg_count || !osd_weights)
     {
         return null;
     }
-    const all_weights = Object.assign({}, ...Object.values(osd_tree));
+    const total_weight = Object.values(osd_weights).reduce((a, c) => Number(a) + Number(c), 0);
-    const total_weight = Object.values(all_weights).reduce((a, c) => Number(a) + Number(c), 0);
+    const all_pgs = Object.values(make_cyclic(combinator.random_combinations(), parity_space));
-    const all_pgs = Object.values(random_combinations(osd_tree, pg_size, max_combinations, parity_space > 1));
     const pg_per_osd = {};
     for (const pg of all_pgs)
     {
@@ -69,15 +69,15 @@ async function optimize_initial({ osd_tree, pg_count, pg_size = 3, pg_minsize =
             pg_per_osd[osd].push((i >= pg_minsize ? parity_space+'*' : '')+"pg_"+pg.join("_"));
         }
     }
-    const pg_effsize = Math.min(pg_minsize, Object.keys(osd_tree).length)
+    let pg_effsize = all_pgs.reduce((a, c) => Math.max(a, c.filter(e => e != NO_OSD).length), 0);
-        + Math.max(0, Math.min(pg_size, Object.keys(osd_tree).length) - pg_minsize) * parity_space;
+    pg_effsize = Math.min(pg_minsize, pg_effsize) + Math.max(0, Math.min(pg_size, pg_effsize) - pg_minsize) * parity_space;
     let lp = '';
     lp += "max: "+all_pgs.map(pg => 'pg_'+pg.join('_')).join(' + ')+";\n";
     for (const osd in pg_per_osd)
     {
         if (osd !== NO_OSD)
         {
-            let osd_pg_count = all_weights[osd]/total_weight*pg_effsize*pg_count;
+            let osd_pg_count = osd_weights[osd]/total_weight*pg_effsize*pg_count;
             lp += pg_per_osd[osd].join(' + ')+' <= '+osd_pg_count+';\n';
         }
     }
@@ -93,7 +93,7 @@ async function optimize_initial({ osd_tree, pg_count, pg_size = 3, pg_minsize =
         throw new Error('Problem is infeasible or unbounded - is it a bug?');
     }
     const int_pgs = make_int_pgs(lp_result.vars, pg_count, ordered);
-    const eff = pg_list_space_efficiency(int_pgs, all_weights, pg_minsize, parity_space);
+    const eff = pg_list_space_efficiency(int_pgs, osd_weights, pg_minsize, parity_space);
     const res = {
         score: lp_result.score,
         weights: lp_result.vars,
@@ -104,6 +104,22 @@ async function optimize_initial({ osd_tree, pg_count, pg_size = 3, pg_minsize =
     return res;
 }
 
+function make_cyclic(pgs, parity_space)
+{
+    if (parity_space > 1)
+    {
+        for (const pg in pgs)
+        {
+            for (let i = 1; i < pg.size; i++)
+            {
+                const cyclic = [ ...pg.slice(i), ...pg.slice(0, i) ];
+                pgs['pg_'+cyclic.join('_')] = cyclic;
+            }
+        }
+    }
+    return pgs;
+}
+
 function shuffle(array)
 {
     for (let i = array.length - 1, j, x; i > 0; i--)
@@ -216,47 +232,17 @@ function calc_intersect_weights(old_pg_size, pg_size, pg_count, prev_weights, al
     return move_weights;
 }
 
-function add_valid_previous(osd_tree, prev_weights, all_pgs)
-{
-    // Add previous combinations that are still valid
-    const hosts = Object.keys(osd_tree).sort();
-    const host_per_osd = {};
-    for (const host in osd_tree)
-    {
-        for (const osd in osd_tree[host])
-        {
-            host_per_osd[osd] = host;
-        }
-    }
-    skip_pg: for (const pg_name in prev_weights)
-    {
-        const seen_hosts = {};
-        const pg = pg_name.substr(3).split(/_/);
-        for (const osd of pg)
-        {
-            if (!host_per_osd[osd] || seen_hosts[host_per_osd[osd]])
-            {
-                continue skip_pg;
-            }
-            seen_hosts[host_per_osd[osd]] = true;
-        }
-        if (!all_pgs[pg_name])
-        {
-            all_pgs[pg_name] = pg;
-        }
-    }
-}
-
 // Try to minimize data movement
-async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3, pg_minsize = 2, max_combinations = 10000, parity_space = 1, ordered = false })
+async function optimize_change({ prev_pgs: prev_int_pgs, osd_weights, combinator, pg_size = 3, pg_minsize = 2, parity_space = 1, ordered = false })
 {
-    if (!osd_tree)
+    if (!osd_weights)
     {
         return null;
     }
     // FIXME: use parity_chunks with parity_space instead of pg_minsize
-    const pg_effsize = Math.min(pg_minsize, Object.keys(osd_tree).length)
+    let all_pgs = make_cyclic(combinator.random_combinations(), parity_space);
-        + Math.max(0, Math.min(pg_size, Object.keys(osd_tree).length) - pg_minsize) * parity_space;
+    let pg_effsize = Object.values(all_pgs).reduce((a, c) => Math.max(a, c.filter(e => e != NO_OSD).length), 0);
+    pg_effsize = Math.min(pg_minsize, pg_effsize) + Math.max(0, Math.min(pg_size, pg_effsize) - pg_minsize) * parity_space;
     const pg_count = prev_int_pgs.length;
     const prev_weights = {};
     const prev_pg_per_osd = {};
@@ -273,10 +259,13 @@ async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3,
     }
     const old_pg_size = prev_int_pgs[0].length;
     // Get all combinations
-    let all_pgs = random_combinations(osd_tree, pg_size, max_combinations, parity_space > 1);
     if (old_pg_size == pg_size)
     {
-        add_valid_previous(osd_tree, prev_weights, all_pgs);
+        const still_valid = combinator.check_combinations(Object.keys(prev_weights).map(pg_name => pg_name.substr(3).split('_')));
+        for (const pg of still_valid)
+        {
+            all_pgs['pg_'+pg.join('_')] = pg;
+        }
     }
     all_pgs = Object.values(all_pgs);
     const pg_per_osd = {};
@@ -295,8 +284,7 @@ async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3,
     // Calculate total weight - old PG weights
     const all_pg_names = all_pgs.map(pg => 'pg_'+pg.join('_'));
     const all_pgs_hash = all_pg_names.reduce((a, c) => { a[c] = true; return a; }, {});
-    const all_weights = Object.assign({}, ...Object.values(osd_tree));
+    const total_weight = Object.values(osd_weights).reduce((a, c) => Number(a) + Number(c), 0);
-    const total_weight = Object.values(all_weights).reduce((a, c) => Number(a) + Number(c), 0);
     // Generate the LP problem
     let lp = '';
     lp += 'max: '+all_pg_names.map(pg_name => (
@@ -311,7 +299,7 @@ async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3,
             )).join(' + ');
             const rm_osd_pg_count = (prev_pg_per_osd[osd]||[])
                 .reduce((a, [ old_pg_name, space ]) => (a + (all_pgs_hash[old_pg_name] ? space : 0)), 0);
-            const osd_pg_count = all_weights[osd]*pg_effsize/total_weight*pg_count - rm_osd_pg_count;
+            const osd_pg_count = osd_weights[osd]*pg_effsize/total_weight*pg_count - rm_osd_pg_count;
             lp += osd_sum + ' <= ' + osd_pg_count + ';\n';
         }
     }
@@ -421,7 +409,7 @@ async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3,
         int_pgs: new_pgs,
         differs,
         osd_differs,
-        space: pg_effsize * pg_list_space_efficiency(new_pgs, all_weights, pg_minsize, parity_space),
+        space: pg_effsize * pg_list_space_efficiency(new_pgs, osd_weights, pg_minsize, parity_space),
         total_space: total_weight,
     };
 }
@@ -502,198 +490,6 @@ function put_aligned_pgs(aligned_pgs, int_pgs, prev_int_pgs, keygen)
     }
 }
 
-// Convert multi-level osd_tree = { level: number|string, id?: string, size?: number, children?: osd_tree }[]
-// levels = { string: number }
-// to a two-level osd_tree suitable for all_combinations()
-function flatten_tree(osd_tree, levels, failure_domain_level, osd_level, domains = {}, i = { i: 1 })
-{
-    osd_level = levels[osd_level] || osd_level;
-    failure_domain_level = levels[failure_domain_level] || failure_domain_level;
-    for (const node of osd_tree)
-    {
-        if ((levels[node.level] || node.level) < failure_domain_level)
-        {
-            flatten_tree(node.children||[], levels, failure_domain_level, osd_level, domains, i);
-        }
-        else
-        {
-            domains['dom'+(i.i++)] = extract_osds([ node ], levels, osd_level);
-        }
-    }
-    return domains;
-}
-
-function extract_osds(osd_tree, levels, osd_level, osds = {})
-{
-    for (const node of osd_tree)
-    {
-        if ((levels[node.level] || node.level) >= osd_level)
-        {
-            osds[node.id] = node.size;
-        }
-        else
-        {
-            extract_osds(node.children||[], levels, osd_level, osds);
-        }
-    }
-    return osds;
-}
-
-// ordered = don't treat (x,y) and (y,x) as equal
-function random_combinations(osd_tree, pg_size, count, ordered)
-{
-    let seed = 0x5f020e43;
-    let rng = () =>
-    {
-        seed ^= seed << 13;
-        seed ^= seed >> 17;
-        seed ^= seed << 5;
-        return seed + 2147483648;
-    };
-    const osds = Object.keys(osd_tree).reduce((a, c) => { a[c] = Object.keys(osd_tree[c]).sort(); return a; }, {});
-    const hosts = Object.keys(osd_tree).sort().filter(h => osds[h].length > 0);
-    const r = {};
-    // Generate random combinations including each OSD at least once
-    for (let h = 0; h < hosts.length; h++)
-    {
-        for (let o = 0; o < osds[hosts[h]].length; o++)
-        {
-            const pg = [ osds[hosts[h]][o] ];
-            const cur_hosts = [ ...hosts ];
-            cur_hosts.splice(h, 1);
-            for (let i = 1; i < pg_size && i < hosts.length; i++)
-            {
-                const next_host = rng() % cur_hosts.length;
-                const next_osd = rng() % osds[cur_hosts[next_host]].length;
-                pg.push(osds[cur_hosts[next_host]][next_osd]);
-                cur_hosts.splice(next_host, 1);
-            }
-            const cyclic_pgs = [ pg ];
-            if (ordered)
-            {
-                for (let i = 1; i < pg.size; i++)
-                {
-                    cyclic_pgs.push([ ...pg.slice(i), ...pg.slice(0, i) ]);
-                }
-            }
-            for (const pg of cyclic_pgs)
-            {
-                while (pg.length < pg_size)
-                {
-                    pg.push(NO_OSD);
-                }
-                r['pg_'+pg.join('_')] = pg;
-            }
-        }
-    }
-    // Generate purely random combinations
-    while (count > 0)
-    {
-        let host_idx = [];
-        const cur_hosts = [ ...hosts.map((h, i) => i) ];
-        const max_hosts = pg_size < hosts.length ? pg_size : hosts.length;
-        if (ordered)
-        {
-            for (let i = 0; i < max_hosts; i++)
-            {
-                const r = rng() % cur_hosts.length;
-                host_idx[i] = cur_hosts[r];
-                cur_hosts.splice(r, 1);
-            }
-        }
-        else
-        {
-            for (let i = 0; i < max_hosts; i++)
-            {
-                const r = rng() % (cur_hosts.length - (max_hosts - i - 1));
-                host_idx[i] = cur_hosts[r];
-                cur_hosts.splice(0, r+1);
-            }
-        }
-        let pg = host_idx.map(h => osds[hosts[h]][rng() % osds[hosts[h]].length]);
-        while (pg.length < pg_size)
-        {
-            pg.push(NO_OSD);
-        }
-        r['pg_'+pg.join('_')] = pg;
-        count--;
-    }
-    return r;
-}
-
-// Super-stupid algorithm. Given the current OSD tree, generate all possible OSD combinations
-// osd_tree = { failure_domain1: { osd1: size1, ... }, ... }
-// ordered = return combinations without duplicates having different order
-function all_combinations(osd_tree, pg_size, ordered, count)
-{
-    const hosts = Object.keys(osd_tree).sort();
-    const osds = Object.keys(osd_tree).reduce((a, c) => { a[c] = Object.keys(osd_tree[c]).sort(); return a; }, {});
-    while (hosts.length < pg_size)
-    {
-        osds[NO_OSD] = [ NO_OSD ];
-        hosts.push(NO_OSD);
-    }
-    let host_idx = [];
-    let osd_idx = [];
-    for (let i = 0; i < pg_size; i++)
-    {
-        host_idx.push(i);
-        osd_idx.push(0);
-    }
-    const r = [];
-    while (!count || count < 0 || r.length < count)
-    {
-        r.push(host_idx.map((hi, i) => osds[hosts[hi]][osd_idx[i]]));
-        let inc = pg_size-1;
-        while (inc >= 0)
-        {
-            osd_idx[inc]++;
-            if (osd_idx[inc] >= osds[hosts[host_idx[inc]]].length)
-            {
-                osd_idx[inc] = 0;
-                inc--;
-            }
-            else
-            {
-                break;
-            }
-        }
-        if (inc < 0)
-        {
-            // no osds left in the current host combination, select the next one
-            inc = pg_size-1;
-            same_again: while (inc >= 0)
-            {
-                host_idx[inc]++;
-                for (let prev_host = 0; prev_host < inc; prev_host++)
-                {
-                    if (host_idx[prev_host] == host_idx[inc])
-                    {
-                        continue same_again;
-                    }
-                }
-                if (host_idx[inc] < (ordered ? hosts.length-(pg_size-1-inc) : hosts.length))
-                {
-                    while ((++inc) < pg_size)
-                    {
-                        host_idx[inc] = (ordered ? host_idx[inc-1]+1 : 0);
-                    }
-                    break;
-                }
-                else
-                {
-                    inc--;
-                }
-            }
-            if (inc < 0)
-            {
-                break;
-            }
-        }
-    }
-    return r;
-}
-
 function pg_weights_space_efficiency(weights, pg_count, osd_sizes)
 {
     const per_osd = {};
@@ -752,11 +548,8 @@ module.exports = {
     pg_weights_space_efficiency,
     pg_list_space_efficiency,
     pg_per_osd_space_efficiency,
-    flatten_tree,
 
     lp_solve,
     make_int_pgs,
     align_pgs,
-    random_combinations,
-    all_combinations,
 };

mon/mon.js

@@ -6,6 +6,8 @@ const http = require('http');
 const crypto = require('crypto');
 const os = require('os');
 const WebSocket = require('ws');
+const { RuleCombinator, parse_level_indexes, parse_pg_dsl } = require('./dsl_pgs.js');
+const { SimpleCombinator, flatten_tree } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 const stableStringify = require('./stable-stringify.js');
 const PGUtil = require('./PGUtil.js');
@@ -63,6 +65,7 @@ const etcd_tree = {
             mon_stats_timeout: 1000, // ms. min: 100
             osd_out_time: 600, // seconds. min: 0
             placement_levels: { datacenter: 1, rack: 2, host: 3, osd: 4, ... },
+            use_old_pg_combinator: false,
             // client and osd
             tcp_header_buffer_size: 65536,
             use_sync_send_recv: false,
@@ -185,7 +188,12 @@ const etcd_tree = {
                 // number of parity chunks, required for EC
                 parity_chunks?: 1,
                 pg_count: 100,
-                failure_domain: 'host',
+                // default is failure_domain=host
+                failure_domain?: 'host',
+                // additional failure domain rules; failure_domain=x is equivalent to x=123..N
+                level_placement?: 'dc=112233 host=123456',
+                raw_placement?: 'any, dc=1 host!=1, dc=1 host!=(1,2)',
+                old_combinator: false,
                 max_osd_combinations: 10000,
                 // block_size, bitmap_granularity, immediate_commit must match all OSDs used in that pool
                 block_size: 131072,
@@ -930,7 +938,6 @@ class Mon
             // Parent's level must be less than child's; OSDs must be leaves
             const parent = parent_level && parent_level < node_level ? node_cfg.parent : '';
             tree[parent].children.push(tree[node_id]);
-            delete node_cfg.parent;
         }
         return { up_osds, levels, osd_tree: tree };
     }
@@ -1096,7 +1103,6 @@ class Mon
         pool_cfg.pg_minsize = Math.floor(pool_cfg.pg_minsize);
         pool_cfg.parity_chunks = Math.floor(pool_cfg.parity_chunks) || undefined;
         pool_cfg.pg_count = Math.floor(pool_cfg.pg_count);
-        pool_cfg.failure_domain = pool_cfg.failure_domain || 'host';
         pool_cfg.max_osd_combinations = Math.floor(pool_cfg.max_osd_combinations) || 10000;
         if (!/^[1-9]\d*$/.exec(''+pool_id))
         {
@@ -1176,10 +1182,32 @@ class Mon
                 console.log('Pool '+pool_id+' has invalid primary_affinity_tags (must be a string or array of strings)');
             return false;
         }
+        if (!this.get_pg_rules(pool_id, pool_cfg, true))
+        {
+            return false;
+        }
         return true;
     }
 
-    filter_osds_by_tags(orig_tree, flat_tree, tags)
+    filter_osds_by_root_node(pool_tree, root_node)
+    {
+        if (!root_node)
+        {
+            return;
+        }
+        pool_tree = pool_tree[pool_cfg.root_node];
+        const cur = [ ...(pool_tree||{}).children||[] ];
+        for (let i = 0; i < cur.length; i++)
+        {
+            if (cur.children)
+            {
+                cur.splice(i+1, 1, ...cur.children);
+            }
+        }
+        return cur;
+    }
+
+    filter_osds_by_tags(orig_tree, tags)
     {
         if (!tags)
         {
@@ -1187,30 +1215,22 @@ class Mon
         }
         for (const tag of (tags instanceof Array ? tags : [ tags ]))
         {
-            for (const host in flat_tree)
+            for (const osd in orig_tree)
             {
-                let found = 0;
+                if (orig_tree[osd].level === 'osd' &&
-                for (const osd in flat_tree[host])
+                    (!orig_tree[osd].tags || !orig_tree[osd].tags[tag]))
                 {
-                    if (!orig_tree[osd].tags || !orig_tree[osd].tags[tag])
+                    delete orig_tree[osd];
-                        delete flat_tree[host][osd];
-                    else
-                        found++;
-                }
-                if (!found)
-                {
-                    delete flat_tree[host];
                 }
             }
         }
     }
 
-    filter_osds_by_block_layout(flat_tree, block_size, bitmap_granularity, immediate_commit)
+    filter_osds_by_block_layout(orig_tree, block_size, bitmap_granularity, immediate_commit)
     {
-        for (const host in flat_tree)
+        for (const osd in orig_tree)
         {
-            let found = 0;
+            if (orig_tree[osd].level === 'osd')
-            for (const osd in flat_tree[host])
             {
                 const osd_stat = this.state.osd.stats[osd];
                 if (osd_stat && (osd_stat.bs_block_size && osd_stat.bs_block_size != block_size ||
@@ -1218,16 +1238,8 @@ class Mon
                     osd_stat.immediate_commit == 'small' && immediate_commit == 'all' ||
                     osd_stat.immediate_commit == 'none' && immediate_commit != 'none'))
                 {
-                    delete flat_tree[host][osd];
+                    delete orig_tree[host][osd];
                 }
-                else
-                {
-                    found++;
-                }
-            }
-            if (!found)
-            {
-                delete flat_tree[host];
             }
         }
     }
@@ -1237,12 +1249,84 @@ class Mon
         let aff_osds = up_osds;
         if (pool_cfg.primary_affinity_tags)
         {
-            aff_osds = { ...up_osds };
+            aff_osds = Object.keys(up_osds).reduce((a, c) => { a[c] = osd_tree[c]; return a; }, {});
-            this.filter_osds_by_tags(osd_tree, { x: aff_osds }, pool_cfg.primary_affinity_tags);
+            this.filter_osds_by_tags(aff_osds, pool_cfg.primary_affinity_tags);
+            for (const osd in aff_osds)
+            {
+                aff_osds[osd] = true;
+            }
         }
         return aff_osds;
     }
 
+    get_pg_rules(pool_id, pool_cfg, warn)
+    {
+        if (pool_cfg.level_placement)
+        {
+            const pg_size = (0|pool_cfg.pg_size);
+            let rules = pool_cfg.level_placement;
+            if (typeof rules === 'string')
+            {
+                rules = rules.split(/\s+/).map(s => s.split(/=/, 2)).reduce((a, c) => { a[c[0]] = c[1]; return a; }, {});
+            }
+            else
+            {
+                rules = { ...rules };
+            }
+            // Always add failure_domain to prevent rules from being totally incorrect
+            const all_diff = [];
+            for (let i = 1; i <= pg_size; i++)
+            {
+                all_diff.push(i);
+            }
+            rules[pool_cfg.failure_domain || 'host'] = all_diff;
+            const levels = this.config.placement_levels||{};
+            levels.host = levels.host || 100;
+            levels.osd = levels.osd || 101;
+            for (const k in rules)
+            {
+                if (!levels[k] || typeof rules[k] !== 'string' &&
+                    (!rules[k] instanceof Array ||
+                    rules[k].filter(s => typeof s !== 'string' && typeof s !== 'number').length > 0))
+                {
+                    if (warn)
+                        console.log('Pool '+pool_id+' configuration is invalid: level_placement should be { [level]: string | (string|number)[] }');
+                    return null;
+                }
+                else if (rules[k].length != pg_size)
+                {
+                    if (warn)
+                        console.log('Pool '+pool_id+' configuration is invalid: values in level_placement should contain exactly pg_size ('+pg_size+') items');
+                    return null;
+                }
+            }
+            return parse_level_indexes(rules);
+        }
+        else if (typeof pool_cfg.raw_placement === 'string')
+        {
+            try
+            {
+                return parse_pg_dsl(pool_cfg.raw_placement);
+            }
+            catch (e)
+            {
+                if (warn)
+                    console.log('Pool '+pool_id+' configuration is invalid: invalid raw_placement: '+e.message);
+            }
+        }
+        else
+        {
+            let rules = [ [] ];
+            let prev = [ 1 ];
+            for (let i = 1; i < pool_cfg.pg_size; i++)
+            {
+                rules.push([ [ pool_cfg.failure_domain||'host', '!=', prev ] ]);
+                prev = [ ...prev, i+1 ];
+            }
+            return rules;
+        }
+    }
+
     async generate_pool_pgs(pool_id, osd_tree, levels)
     {
         const pool_cfg = this.state.config.pools[pool_id];
@@ -1250,10 +1334,9 @@ class Mon
         {
             return null;
         }
-        let pool_tree = osd_tree[pool_cfg.root_node || ''];
+        let pool_tree = osd_tree;
-        pool_tree = pool_tree ? pool_tree.children : [];
+        this.filter_osds_by_root_node(pool_tree, pool_cfg.root_node);
-        pool_tree = LPOptimizer.flatten_tree(pool_tree, levels, pool_cfg.failure_domain, 'osd');
+        this.filter_osds_by_tags(pool_tree, pool_cfg.osd_tags);
-        this.filter_osds_by_tags(osd_tree, pool_tree, pool_cfg.osd_tags);
         this.filter_osds_by_block_layout(
             pool_tree,
             pool_cfg.block_size || this.config.block_size || 131072,
@@ -1276,11 +1359,15 @@ class Mon
         }
         const old_pg_count = prev_pgs.length;
         const optimize_cfg = {
-            osd_tree: pool_tree,
+            osd_weights: Object.values(pool_tree).filter(item => item.level === 'osd').reduce((a, c) => { a[c.id] = c.size; return a; }, {}),
+            combinator: !this.config.use_old_pg_combinator || pool_cfg.level_placement || pool_cfg.raw_placement
+                // new algorithm:
+                ? new RuleCombinator(osd_tree, this.get_pg_rules(pool_id, pool_cfg), pool_cfg.max_osd_combinations)
+                // old algorithm:
+                : new SimpleCombinator(flatten_tree(osd_tree[''].children, levels, pool_cfg.failure_domain, 'osd'), pool_cfg.pg_size, pool_cfg.max_osd_combinations),
             pg_count: pool_cfg.pg_count,
             pg_size: pool_cfg.pg_size,
             pg_minsize: pool_cfg.pg_minsize,
-            max_combinations: pool_cfg.max_osd_combinations,
             ordered: pool_cfg.scheme != 'replicated',
         };
         let optimize_result;

mon/murmur3.js

@@ -0,0 +1,38 @@
+function select_murmur3(count, cb)
+{
+    if (!count)
+    {
+        return null;
+    }
+    else
+    {
+        let i = 0, maxh = -1;
+        for (let j = 0; j < count; j++)
+        {
+            const h = murmur3(cb(j));
+            if (h > maxh)
+            {
+                i = j;
+                maxh = h;
+            }
+        }
+        return i;
+    }
+}
+
+function murmur3(s)
+{
+    let hash = 0x12345678;
+    for (let i = 0; i < s.length; i++)
+    {
+        hash ^= s.charCodeAt(i);
+        hash = (hash*0x5bd1e995) & 0xFFFFFFFF;
+        hash ^= (hash >> 15);
+    }
+    return hash;
+}
+
+module.exports = {
+    murmur3,
+    select_murmur3,
+};

mon/simple_pgs.js

@@ -0,0 +1,241 @@
+const { select_murmur3 } = require('./murmur3.js');
+
+const NO_OSD = 'Z';
+
+class SimpleCombinator
+{
+    constructor(flat_tree, pg_size, max_combinations, ordered)
+    {
+        this.osd_tree = flat_tree;
+        this.pg_size = pg_size;
+        this.max_combinations = max_combinations;
+        this.ordered = ordered;
+    }
+
+    random_combinations()
+    {
+        return random_combinations(this.osd_tree, this.pg_size, this.max_combinations, this.ordered);
+    }
+
+    check_combinations(pgs)
+    {
+        return check_combinations(this.osd_tree, pgs);
+    }
+}
+
+// Convert multi-level osd_tree = { level: number|string, id?: string, size?: number, children?: osd_tree }[]
+// levels = { string: number }
+// to a two-level osd_tree suitable for all_combinations()
+function flatten_tree(osd_tree, levels, failure_domain_level, osd_level, domains = {}, i = { i: 1 })
+{
+    osd_level = levels[osd_level] || osd_level;
+    failure_domain_level = levels[failure_domain_level] || failure_domain_level;
+    for (const node of osd_tree)
+    {
+        if ((levels[node.level] || node.level) < failure_domain_level)
+        {
+            flatten_tree(node.children||[], levels, failure_domain_level, osd_level, domains, i);
+        }
+        else
+        {
+            domains['dom'+(i.i++)] = extract_osds([ node ], levels, osd_level);
+        }
+    }
+    return domains;
+}
+
+function extract_osds(osd_tree, levels, osd_level, osds = {})
+{
+    for (const node of osd_tree)
+    {
+        if ((levels[node.level] || node.level) >= osd_level)
+        {
+            osds[node.id] = node.size;
+        }
+        else
+        {
+            extract_osds(node.children||[], levels, osd_level, osds);
+        }
+    }
+    return osds;
+}
+
+// ordered = don't treat (x,y) and (y,x) as equal
+function random_combinations(osd_tree, pg_size, count, ordered)
+{
+    const osds = Object.keys(osd_tree).reduce((a, c) => { a[c] = Object.keys(osd_tree[c]).sort(); return a; }, {});
+    const hosts = Object.keys(osd_tree).sort().filter(h => osds[h].length > 0);
+    const r = {};
+    // Generate random combinations including each OSD at least once
+    for (let h = 0; h < hosts.length; h++)
+    {
+        for (let o = 0; o < osds[hosts[h]].length; o++)
+        {
+            const pg = [ osds[hosts[h]][o] ];
+            const cur_hosts = [ ...hosts ];
+            cur_hosts.splice(h, 1);
+            for (let i = 1; i < pg_size && i < hosts.length; i++)
+            {
+                const next_host = select_murmur3(cur_hosts.length, i => pg[0]+':i:'+cur_hosts[i]);
+                const next_osd = select_murmur3(osds[cur_hosts[next_host]].length, i => pg[0]+':i:'+osds[cur_hosts[next_host]][i]);
+                pg.push(osds[cur_hosts[next_host]][next_osd]);
+                cur_hosts.splice(next_host, 1);
+            }
+            while (pg.length < pg_size)
+            {
+                pg.push(NO_OSD);
+            }
+            r['pg_'+pg.join('_')] = pg;
+        }
+    }
+    // Generate purely random combinations
+    while (count > 0)
+    {
+        let host_idx = [];
+        const cur_hosts = [ ...hosts.map((h, i) => i) ];
+        const max_hosts = pg_size < hosts.length ? pg_size : hosts.length;
+        if (ordered)
+        {
+            for (let i = 0; i < max_hosts; i++)
+            {
+                const r = select_murmur3(cur_hosts.length, i => count+':h:'+cur_hosts[i]);
+                host_idx[i] = cur_hosts[r];
+                cur_hosts.splice(r, 1);
+            }
+        }
+        else
+        {
+            for (let i = 0; i < max_hosts; i++)
+            {
+                const r = select_murmur3(cur_hosts.length - (max_hosts - i - 1), i => count+':h:'+cur_hosts[i]);
+                host_idx[i] = cur_hosts[r];
+                cur_hosts.splice(0, r+1);
+            }
+        }
+        let pg = host_idx.map(h => osds[hosts[h]][select_murmur3(osds[hosts[h]].length, i => count+':o:'+osds[hosts[h]][i])]);
+        while (pg.length < pg_size)
+        {
+            pg.push(NO_OSD);
+        }
+        r['pg_'+pg.join('_')] = pg;
+        count--;
+    }
+    return r;
+}
+
+// Super-stupid algorithm. Given the current OSD tree, generate all possible OSD combinations
+// osd_tree = { failure_domain1: { osd1: size1, ... }, ... }
+// ordered = return combinations without duplicates having different order
+function all_combinations(osd_tree, pg_size, ordered, count)
+{
+    const hosts = Object.keys(osd_tree).sort();
+    const osds = Object.keys(osd_tree).reduce((a, c) => { a[c] = Object.keys(osd_tree[c]).sort(); return a; }, {});
+    while (hosts.length < pg_size)
+    {
+        osds[NO_OSD] = [ NO_OSD ];
+        hosts.push(NO_OSD);
+    }
+    let host_idx = [];
+    let osd_idx = [];
+    for (let i = 0; i < pg_size; i++)
+    {
+        host_idx.push(i);
+        osd_idx.push(0);
+    }
+    const r = [];
+    while (!count || count < 0 || r.length < count)
+    {
+        r.push(host_idx.map((hi, i) => osds[hosts[hi]][osd_idx[i]]));
+        let inc = pg_size-1;
+        while (inc >= 0)
+        {
+            osd_idx[inc]++;
+            if (osd_idx[inc] >= osds[hosts[host_idx[inc]]].length)
+            {
+                osd_idx[inc] = 0;
+                inc--;
+            }
+            else
+            {
+                break;
+            }
+        }
+        if (inc < 0)
+        {
+            // no osds left in the current host combination, select the next one
+            inc = pg_size-1;
+            same_again: while (inc >= 0)
+            {
+                host_idx[inc]++;
+                for (let prev_host = 0; prev_host < inc; prev_host++)
+                {
+                    if (host_idx[prev_host] == host_idx[inc])
+                    {
+                        continue same_again;
+                    }
+                }
+                if (host_idx[inc] < (ordered ? hosts.length-(pg_size-1-inc) : hosts.length))
+                {
+                    while ((++inc) < pg_size)
+                    {
+                        host_idx[inc] = (ordered ? host_idx[inc-1]+1 : 0);
+                    }
+                    break;
+                }
+                else
+                {
+                    inc--;
+                }
+            }
+            if (inc < 0)
+            {
+                break;
+            }
+        }
+    }
+    return r;
+}
+
+function check_combinations(osd_tree, pgs)
+{
+    const hosts = Object.keys(osd_tree).sort();
+    const host_per_osd = {};
+    for (const host in osd_tree)
+    {
+        for (const osd in osd_tree[host])
+        {
+            host_per_osd[osd] = host;
+        }
+    }
+    const res = [];
+    skip_pg: for (const pg of pgs)
+    {
+        const seen_hosts = {};
+        for (const osd of pg)
+        {
+            if (!host_per_osd[osd] || seen_hosts[host_per_osd[osd]])
+            {
+                continue skip_pg;
+            }
+            seen_hosts[host_per_osd[osd]] = true;
+        }
+        res.push(pg);
+    }
+    return res;
+}
+
+function compat(params)
+{
+    return {
+        ...params,
+        osd_weights: Object.assign({}, ...Object.values(params.osd_tree)),
+        combinator: new SimpleCombinator(params.osd_tree, params.pg_size, params.max_combinations||10000),
+    };
+}
+
+module.exports = {
+    flatten_tree,
+    SimpleCombinator,
+    compat,
+    NO_OSD,
+};

mon/test-nonuniform.js

@@ -7,6 +7,7 @@
 // This leads to really uneven OSD fill ratio in Ceph even when PGs are perfectly balanced.
 // But we support this case with the "parity_space" parameter in optimize_initial()/optimize_change().
 
+const { SimpleCombinator } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 
 const osd_tree = {
@@ -114,16 +115,17 @@ Fine, let's try to optimize for it.
 
 async function run()
 {
-    const all_weights = Object.assign({}, ...Object.values(osd_tree));
+    const osd_weights = Object.assign({}, ...Object.values(osd_tree));
-    const total_weight = Object.values(all_weights).reduce((a, c) => Number(a) + Number(c), 0);
+    const total_weight = Object.values(osd_weights).reduce((a, c) => Number(a) + Number(c), 0);
-    const eff = LPOptimizer.pg_list_space_efficiency(prev_pgs, all_weights, 2, 2.26);
+    const eff = LPOptimizer.pg_list_space_efficiency(prev_pgs, osd_weights, 2, 2.26);
     const orig = eff*4.26 / total_weight;
     console.log('Original efficiency was: '+Math.round(orig*10000)/100+' %');
 
-    let prev = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 3, pg_count: 256, parity_space: 2.26 });
+    const combinator = new SimpleCombinator(osd_tree, 3, 10000);
+    let prev = await LPOptimizer.optimize_initial({ osd_weights, combinator, pg_size: 3, pg_count: 256, parity_space: 2.26 });
     LPOptimizer.print_change_stats(prev);
 
-    let next = await LPOptimizer.optimize_change({ prev_pgs, osd_tree, pg_size: 3, max_combinations: 10000, parity_space: 2.26 });
+    let next = await LPOptimizer.optimize_change({ prev_pgs, osd_weights, combinator, pg_size: 3, parity_space: 2.26 });
     LPOptimizer.print_change_stats(next);
 }
 

mon/test-optimize-simple.js

@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+const { compat } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 
 async function run()
@@ -14,26 +15,26 @@ async function run()
     let res;
 
     console.log('16 PGs, size=3');
-    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 3, pg_count: 16, ordered: false });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree, pg_size: 3, pg_count: 16, ordered: false }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 3, 'Initial distribution');
     console.log('\nChange size to 2');
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2, ordered: false });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2, ordered: false }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space >= 3*14/16 && res.osd_differs == 0, 'Redistribution');
     console.log('\nRemove OSD 3');
     const no3_tree = { ...osd_tree };
     delete no3_tree['300'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: no3_tree, pg_size: 2, ordered: false });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: no3_tree, pg_size: 2, ordered: false }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 2, 'Redistribution after OSD removal');
 
     console.log('\n16 PGs, size=3, ordered');
-    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 3, pg_count: 16, ordered: true });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree, pg_size: 3, pg_count: 16, ordered: true }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 3, 'Initial distribution');
     console.log('\nChange size to 2, ordered');
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2, ordered: true });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2, ordered: true }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space >= 3*14/16 && res.osd_differs < 8, 'Redistribution');
 }

mon/test-optimize-undersized.js

@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+const { compat, flatten_tree } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 
 const crush_tree = [
@@ -36,44 +37,44 @@ const crush_tree = [
     ] },
 ];
 
-const osd_tree = LPOptimizer.flatten_tree(crush_tree, {}, 1, 3);
+const osd_tree = flatten_tree(crush_tree, {}, 1, 3);
 console.log(osd_tree);
 
 async function run()
 {
     const cur_tree = {};
     console.log('Empty tree:');
-    let res = await LPOptimizer.optimize_initial({ osd_tree: cur_tree, pg_size: 3, pg_count: 256 });
+    let res = await LPOptimizer.optimize_initial(compat({ osd_tree: cur_tree, pg_size: 3, pg_count: 256 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 0);
     console.log('\nAdding 1st failure domain:');
     cur_tree['dom1'] = osd_tree['dom1'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 12 && res.total_space == 12);
     console.log('\nAdding 2nd failure domain:');
     cur_tree['dom2'] = osd_tree['dom2'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 24 && res.total_space == 24);
     console.log('\nAdding 3rd failure domain:');
     cur_tree['dom3'] = osd_tree['dom3'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 36 && res.total_space == 36);
     console.log('\nRemoving 3rd failure domain:');
     delete cur_tree['dom3'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 24 && res.total_space == 24);
     console.log('\nRemoving 2nd failure domain:');
     delete cur_tree['dom2'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 12 && res.total_space == 12);
     console.log('\nRemoving 1st failure domain:');
     delete cur_tree['dom1'];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree: cur_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     assert(res.space == 0);
 }

mon/test-optimize-unfeasible.js

@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+const { compat } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 
 const osd_tree = {
@@ -20,13 +21,13 @@ async function run()
 {
     let res;
     console.log('256 PGs, 3+3 OSDs, size=2');
-    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 2, pg_count: 256 });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree, pg_size: 2, pg_count: 256 }));
     LPOptimizer.print_change_stats(res, false);
 
     // Should NOT fail with the "unfeasible or unbounded" exception
     console.log('\nRemoving osd.2');
     delete osd_tree[100][2];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 }));
     LPOptimizer.print_change_stats(res, false);
 }
 

mon/test-optimize.js

@@ -1,6 +1,7 @@
 // Copyright (c) Vitaliy Filippov, 2019+
 // License: VNPL-1.1 (see README.md for details)
 
+const { compat, flatten_tree } = require('./simple_pgs.js');
 const LPOptimizer = require('./lp-optimizer.js');
 
 const osd_tree = {
@@ -84,31 +85,31 @@ async function run()
     // Space efficiency is ~99% in all cases.
 
     console.log('256 PGs, size=2');
-    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 2, pg_count: 256 });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree, pg_size: 2, pg_count: 256 }));
     LPOptimizer.print_change_stats(res, false);
     console.log('\nAdding osd.8');
     osd_tree[500][8] = 3.58589;
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 }));
     LPOptimizer.print_change_stats(res, false);
     console.log('\nRemoving osd.8');
     delete osd_tree[500][8];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 }));
     LPOptimizer.print_change_stats(res, false);
 
     console.log('\n256 PGs, size=3');
-    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 3, pg_count: 256 });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree, pg_size: 3, pg_count: 256 }));
     LPOptimizer.print_change_stats(res, false);
     console.log('\nAdding osd.8');
     osd_tree[500][8] = 3.58589;
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
     console.log('\nRemoving osd.8');
     delete osd_tree[500][8];
-    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 3 });
+    res = await LPOptimizer.optimize_change(compat({ prev_pgs: res.int_pgs, osd_tree, pg_size: 3 }));
     LPOptimizer.print_change_stats(res, false);
 
     console.log('\n256 PGs, size=3, failure domain=rack');
-    res = await LPOptimizer.optimize_initial({ osd_tree: LPOptimizer.flatten_tree(crush_tree, {}, 1, 3), pg_size: 3, pg_count: 256 });
+    res = await LPOptimizer.optimize_initial(compat({ osd_tree: flatten_tree(crush_tree, {}, 1, 3), pg_size: 3, pg_count: 256 }));
     LPOptimizer.print_change_stats(res, false);
 }
 

mon/test-parse-dsl.js

@@ -0,0 +1,118 @@
+const { random_custom_combinations, index_tree, parse_level_indexes, parse_pg_dsl } = require('./dsl_pgs.js');
+
+function check(result, expected)
+{
+    console.dir(result, { depth: null });
+    if (JSON.stringify(result) !== JSON.stringify(expected))
+    {
+        process.stderr.write('Unexpected value, expected: ');
+        console.dir(expected, { depth: null });
+        process.exit(1);
+    }
+}
+
+check(
+    parse_pg_dsl("any, dc=1 host!=1, dc!=1, dc=3 host!=3, dc!=(1,3), dc=5 host!=5"),
+    [
+        [],
+        [ [ 'dc', '=', 1 ], [ 'host', '!=', 1 ] ],
+        [ [ 'dc', '!=', 1 ] ],
+        [ [ 'dc', '=', 3 ], [ 'host', '!=', 3 ] ],
+        [ [ 'dc', '!=', [ 1, 3 ] ] ],
+        [ [ 'dc', '=', 5 ], [ 'host', '!=', 5 ] ],
+    ]
+);
+
+check(
+    parse_pg_dsl("dc=meow, dc!=1, dc>2"),
+    [
+        [ [ 'dc', '=', { id: 'meow' } ] ],
+        [ [ 'dc', '!=', 1 ] ],
+        [ [ 'dc', '>', 2 ] ],
+    ]
+);
+
+check(
+    parse_level_indexes({ dc: '112233', host: 'ABCDEF' }),
+    [
+        [],
+        [ [ 'dc', '=', 1 ],         [ 'host', '!=', [ 1 ] ] ],
+        [ [ 'dc', '!=', [ 1 ] ],    [ 'host', '!=', [ 1, 2 ] ] ],
+        [ [ 'dc', '=', 3 ],         [ 'host', '!=', [ 1, 2, 3 ] ] ],
+        [ [ 'dc', '!=', [ 1, 3 ] ], [ 'host', '!=', [ 1, 2, 3, 4 ] ] ],
+        [ [ 'dc', '=', 5 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5 ] ] ],
+    ]
+);
+
+check(
+    parse_level_indexes({ dc: '112233', host: 'ABCDEF' }, [ 'dc', 'host' ]),
+    [
+        [],
+        [ [ 'dc', '=', 1 ],         [ 'host', '!=', [ 1 ] ] ],
+        [ [ 'dc', '!=', [ 1 ] ] ],
+        [ [ 'dc', '=', 3 ],         [ 'host', '!=', [ 3 ] ] ],
+        [ [ 'dc', '!=', [ 1, 3 ] ] ],
+        [ [ 'dc', '=', 5 ],         [ 'host', '!=', [ 5 ] ] ],
+    ]
+);
+
+check(
+    parse_level_indexes({ dc: '112211223333', host: '123456789ABC' }),
+    [
+        [],
+        [ [ 'dc', '=', 1 ],         [ 'host', '!=', [ 1 ] ] ],
+        [ [ 'dc', '!=', [ 1 ] ],    [ 'host', '!=', [ 1, 2 ] ] ],
+        [ [ 'dc', '=', 3 ],         [ 'host', '!=', [ 1, 2, 3 ] ] ],
+        [ [ 'dc', '=', 1 ],         [ 'host', '!=', [ 1, 2, 3, 4 ] ] ],
+        [ [ 'dc', '=', 1 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5 ] ] ],
+        [ [ 'dc', '=', 3 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5, 6 ] ] ],
+        [ [ 'dc', '=', 3 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5, 6, 7 ] ] ],
+        [ [ 'dc', '!=', [ 1, 3 ] ], [ 'host', '!=', [ 1, 2, 3, 4, 5, 6, 7, 8 ] ] ],
+        [ [ 'dc', '=', 9 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5, 6, 7, 8, 9 ] ] ],
+        [ [ 'dc', '=', 9 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ] ] ],
+        [ [ 'dc', '=', 9 ],         [ 'host', '!=', [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 ] ] ],
+    ]
+);
+
+check(
+    parse_level_indexes({ dc: '112211223333', host: '123456789ABC' }, [ 'dc', 'host' ]),
+    [
+        [],
+        [ [ 'dc', '=', 1 ], [ 'host', '!=', [ 1 ] ] ],
+        [ [ 'dc', '!=', [ 1 ] ] ],
+        [ [ 'dc', '=', 3 ], [ 'host', '!=', [ 3 ] ] ],
+        [ [ 'dc', '=', 1 ], [ 'host', '!=', [ 1, 2 ] ] ],
+        [ [ 'dc', '=', 1 ], [ 'host', '!=', [ 1, 2, 5 ] ] ],
+        [ [ 'dc', '=', 3 ], [ 'host', '!=', [ 3, 4 ] ] ],
+        [ [ 'dc', '=', 3 ], [ 'host', '!=', [ 3, 4, 7 ] ] ],
+        [ [ 'dc', '!=', [ 1, 3 ] ] ],
+        [ [ 'dc', '=', 9 ], [ 'host', '!=', [ 9 ] ] ],
+        [ [ 'dc', '=', 9 ], [ 'host', '!=', [ 9, 10 ] ] ],
+        [ [ 'dc', '=', 9 ], [ 'host', '!=', [ 9, 10, 11 ] ] ]
+    ]
+);
+
+check(
+    Object.keys(random_custom_combinations(index_tree([
+        { id: '1', size: 1, level: 'osd' },
+        { id: '2', size: 2, level: 'osd' },
+        { id: '3', size: 3, level: 'osd' }
+    ]), parse_level_indexes({ osd: '12' }), 10000)).sort(),
+    [ 'pg_1_2', 'pg_1_3', 'pg_2_3' ]
+);
+
+check(
+    Object.keys(random_custom_combinations(index_tree([
+        { id: 'h1', level: 'host' },
+        { id: 'h2', level: 'host' },
+        { id: 'h3', level: 'host' },
+        { id: '1', size: 1, level: 'osd', parent: 'h1' },
+        { id: '2', size: 1, level: 'osd', parent: 'h2' },
+        { id: '3', size: 1, level: 'osd', parent: 'h2' },
+        { id: '4', size: 1, level: 'osd', parent: 'h3' },
+        { id: '5', size: 1, level: 'osd', parent: 'h3' },
+    ]), parse_level_indexes({ host: '1122', osd: '1234' }), 10000)).sort(),
+    [ 'pg_2_3_4_5' ]
+);
+
+console.log('OK');

src/cli.cpp

@@ -129,6 +129,8 @@ static const char* help_text =
     "    --block_size 128k             Put pool only on OSDs with this data block size\n"
     "    --bitmap_granularity 4k       Put pool only on OSDs with this logical sector size\n"
     "    --immediate_commit none       Put pool only on OSDs with this or larger immediate_commit (none < small < all)\n"
+    "    --level_placement <rules>     Use additional failure domain rules (example: \"dc=112233\")\n"
+    "    --raw_placement <rules>       Specify raw PG generation rules (see documentation for details)\n"
     "    --primary_affinity_tags tags  Prefer to put primary copies on OSDs with all specified tags\n"
     "    --scrub_interval <time>       Enable regular scrubbing for this pool. Format: number + unit s/m/h/d/M/y\n"
     "    --used_for_fs <name>          Mark pool as used for VitastorFS with metadata in image <name>\n"
@@ -145,6 +147,7 @@ static const char* help_text =
     "    [-s|--pg_size <number>] [--pg_minsize <number>] [-n|--pg_count <count>]\n"
     "    [--failure_domain <level>] [--root_node <node>] [--osd_tags <tags>] [--used_for_fs <name>]\n"
     "    [--max_osd_combinations <number>] [--primary_affinity_tags <tags>] [--scrub_interval <time>]\n"
+    "    [--level_placement <rules>] [--raw_placement <rules>]\n"
     "  Non-modifiable parameters (changing them WILL lead to data loss):\n"
     "    [--block_size <size>] [--bitmap_granularity <size>]\n"
     "    [--immediate_commit <all|small|none>] [--pg_stripe_size <size>]\n"

src/cli_pool_cfg.cpp

@@ -82,9 +82,38 @@ std::string validate_pool_config(json11::Json::object & new_cfg, json11::Json ol
             value = value.uint64_value();
         }
         else if (key == "name" || key == "scheme" || key == "immediate_commit" ||
-            key == "failure_domain" || key == "root_node" || key == "scrub_interval" || key == "used_for_fs")
+            key == "failure_domain" || key == "root_node" || key == "scrub_interval" || key == "used_for_fs" ||
+            key == "raw_placement")
         {
-            // OK
+            if (!value.is_string())
+            {
+                return key+" must be a string";
+            }
+        }
+        else if (key == "level_placement")
+        {
+            // level=rule, level=rule, ...
+            if (!value.is_object())
+            {
+                json11::Json::object obj;
+                for (auto & item: explode(",", value.string_value(), true))
+                {
+                    auto pair = explode("=", item, true);
+                    if (pair.size() >= 2)
+                    {
+                        obj[pair[0]] = pair[1];
+                    }
+                }
+                if (obj.size())
+                {
+                    value = obj;
+                }
+                else
+                {
+                    new_cfg.erase(kv_it++);
+                    continue;
+                }
+            }
         }
         else if (key == "osd_tags" || key == "primary_affinity_tags")
         {
@@ -184,6 +213,38 @@ std::string validate_pool_config(json11::Json::object & new_cfg, json11::Json ol
         return "PG size can't be greater than 256";
     }
 
+    // PG rules
+    if (!cfg["level_placement"].is_null())
+    {
+        for (auto & lr: cfg["level_placement"].object_items())
+        {
+            int len = 0;
+            if (lr.second.is_array())
+            {
+                for (auto & lri: lr.second.array_items())
+                {
+                    if (!lri.is_string() && !lri.is_number())
+                    {
+                        return "--level_placement contains an array with non-scalar value: "+lri.dump();
+                    }
+                }
+                len = lr.second.array_items().size();
+            }
+            else if (!lr.second.is_string())
+            {
+                return "--level_placement contains a non-array and non-string value: "+lr.second.dump();
+            }
+            else
+            {
+                len = lr.second.string_value().size();
+            }
+            if (len != pg_size)
+            {
+                return "values in --level_placement should be exactly pg_size ("+std::to_string(pg_size)+") long";
+            }
+        }
+    }
+
     // parity_chunks
     uint64_t parity_chunks = 1;
     if (scheme == POOL_SCHEME_EC)