minio/vendor/github.com/klauspost/reedsolomon/options.go
Harshavardhana c0721164be Automatically set goroutines based on shardSize (#5346)
Update reedsolomon library to enable feature to automatically
set number of go-routines based on the input shard size,
since shard size is sort of a constant in Minio for
objects > 10MiB (default blocksize)

klauspost reported around 15-20% improvement in performance
numbers on older systems such as AVX and SSE3

```
name                  old speed      new speed      delta
Encode10x2x10000-8    5.45GB/s ± 1%  6.22GB/s ± 1%  +14.20%    (p=0.000 n=9+9)
Encode100x20x10000-8  1.44GB/s ± 1%  1.64GB/s ± 1%  +13.77%  (p=0.000 n=10+10)
Encode17x3x1M-8       10.0GB/s ± 5%  12.0GB/s ± 1%  +19.88%  (p=0.000 n=10+10)
Encode10x4x16M-8      7.81GB/s ± 5%  8.56GB/s ± 5%   +9.58%   (p=0.000 n=10+9)
Encode5x2x1M-8        15.3GB/s ± 2%  19.6GB/s ± 2%  +28.57%   (p=0.000 n=9+10)
Encode10x2x1M-8       12.2GB/s ± 5%  15.0GB/s ± 5%  +22.45%  (p=0.000 n=10+10)
Encode10x4x1M-8       7.84GB/s ± 1%  9.03GB/s ± 1%  +15.19%    (p=0.000 n=9+9)
Encode50x20x1M-8      1.73GB/s ± 4%  2.09GB/s ± 4%  +20.59%   (p=0.000 n=10+9)
Encode17x3x16M-8      10.6GB/s ± 1%  11.7GB/s ± 4%  +10.12%   (p=0.000 n=8+10)
```
2018-01-03 13:47:22 -08:00

112 lines
2.8 KiB
Go

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
shardSize int
}
var defaultOptions = options{
maxGoroutines: 384,
minSplitSize: 1024,
}
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
}
}
}
// WithAutoGoroutines will adjust the number of goroutines for optimal speed with a
// specific shard size.
// Send in the shard size you expect to send. Other shard sizes will work, but may not
// run at the optimal speed.
// Overwrites WithMaxGoroutines.
// If shardSize <= 0, it is ignored.
func WithAutoGoroutines(shardSize int) Option {
return func(o *options) {
o.shardSize = shardSize
}
}
// 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
}
}