Add note about NBD
parent
7619a789c0
commit
f460d8c1c8
14
README.md
14
README.md
|
@ -244,6 +244,20 @@ Vitastor was configured with: `--disable_data_fsync true --immediate_commit all
|
||||||
--journal_no_same_sector_overwrites true --journal_sector_buffer_count 1024
|
--journal_no_same_sector_overwrites true --journal_sector_buffer_count 1024
|
||||||
--journal_size 16777216`.
|
--journal_size 16777216`.
|
||||||
|
|
||||||
|
### NBD
|
||||||
|
|
||||||
|
NBD is currently required to mount Vitastor via kernel, but it imposes additional overhead
|
||||||
|
due to additional copying between the kernel and userspace. This mostly hurts linear
|
||||||
|
bandwidth, not iops.
|
||||||
|
|
||||||
|
Vitastor with single-thread NBD on the same hardware:
|
||||||
|
- T1Q1 write: 6000 iops (0.166ms latency)
|
||||||
|
- T1Q1 read: 5518 iops (0.18ms latency)
|
||||||
|
- T1Q128 write: 94400 iops
|
||||||
|
- T1Q128 read: 103000 iops
|
||||||
|
- Linear write (4M T1Q128): 1266 MB/s (compared to 2600 MB/s via fio)
|
||||||
|
- Linear read (4M T1Q128): 975 MB/s (compared to 1400 MB/s via fio)
|
||||||
|
|
||||||
## Building
|
## Building
|
||||||
|
|
||||||
- Install Linux kernel 5.4 or newer for io_uring support.
|
- Install Linux kernel 5.4 or newer for io_uring support.
|
||||||
|
|
Loading…
Reference in New Issue