package reedsolomon import ( "runtime" "github.com/klauspost/cpuid" ) // Option allows to override processing parameters. type Option func(*options) type options struct { maxGoroutines int minSplitSize int useAVX2, useSSSE3, useSSE2 bool usePAR1Matrix bool useCauchy bool } var defaultOptions = options{ maxGoroutines: 384, minSplitSize: 512, } func init() { if runtime.GOMAXPROCS(0) <= 1 { defaultOptions.maxGoroutines = 1 } // Detect CPU capabilities. defaultOptions.useSSSE3 = cpuid.CPU.SSSE3() defaultOptions.useAVX2 = cpuid.CPU.AVX2() defaultOptions.useSSE2 = cpuid.CPU.SSE2() } // WithMaxGoroutines is the maximum number of goroutines number for encoding & decoding. // Jobs will be split into this many parts, unless each goroutine would have to process // less than minSplitSize bytes (set with WithMinSplitSize). // For the best speed, keep this well above the GOMAXPROCS number for more fine grained // scheduling. // If n <= 0, it is ignored. func WithMaxGoroutines(n int) Option { return func(o *options) { if n > 0 { o.maxGoroutines = n } } } // WithMinSplitSize is the minimum encoding size in bytes per goroutine. // See WithMaxGoroutines on how jobs are split. // If n <= 0, it is ignored. func WithMinSplitSize(n int) Option { return func(o *options) { if n > 0 { o.minSplitSize = n } } } func withSSE3(enabled bool) Option { return func(o *options) { o.useSSSE3 = enabled } } func withAVX2(enabled bool) Option { return func(o *options) { o.useAVX2 = enabled } } func withSSE2(enabled bool) Option { return func(o *options) { o.useSSE2 = enabled } } // WithPAR1Matrix causes the encoder to build the matrix how PARv1 // does. Note that the method they use is buggy, and may lead to cases // where recovery is impossible, even if there are enough parity // shards. func WithPAR1Matrix() Option { return func(o *options) { o.usePAR1Matrix = true o.useCauchy = false } } // WithCauchyMatrix will make the encoder build a Cauchy style matrix. // The output of this is not compatible with the standard output. // A Cauchy matrix is faster to generate. This does not affect data throughput, // but will result in slightly faster start-up time. func WithCauchyMatrix() Option { return func(o *options) { o.useCauchy = true o.usePAR1Matrix = false } }