[#754] blobstor: Estimate compressability

Now it is possible to enable compressability estimation.
If data is likely uncompressable, it should reduce CPU time and memory.

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>
This commit is contained in:
Dmitrii Stepanov 2023-10-31 14:45:22 +03:00
parent 05b508f79a
commit c80b46fad3
11 changed files with 153 additions and 12 deletions

View file

@ -106,6 +106,9 @@ type applicationConfiguration struct {
type shardCfg struct {
compress bool
estimateCompressibility bool
estimateCompressibilityThreshold float64
smallSizeObjectLimit uint64
uncompressableContentType []string
refillMetabase bool
@ -217,6 +220,8 @@ func (a *applicationConfiguration) updateShardConfig(c *config.Config, oldConfig
newConfig.refillMetabase = oldConfig.RefillMetabase()
newConfig.mode = oldConfig.Mode()
newConfig.compress = oldConfig.Compress()
newConfig.estimateCompressibility = oldConfig.EstimateCompressibility()
newConfig.estimateCompressibilityThreshold = oldConfig.EstimateCompressibilityThreshold()
newConfig.uncompressableContentType = oldConfig.UncompressableContentTypes()
newConfig.smallSizeObjectLimit = oldConfig.SmallSizeLimit()
@ -830,6 +835,8 @@ func (c *cfg) getShardOpts(shCfg shardCfg) shardOptsWithID {
blobstoreOpts := []blobstor.Option{
blobstor.WithCompressObjects(shCfg.compress),
blobstor.WithUncompressableContentTypes(shCfg.uncompressableContentType),
blobstor.WithCompressibilityEstimate(shCfg.estimateCompressibility),
blobstor.WithCompressibilityEstimateThreshold(shCfg.estimateCompressibilityThreshold),
blobstor.WithStorages(ss),
blobstor.WithLogger(c.log),
}

View file

@ -223,3 +223,15 @@ func parseSizeInBytes(sizeStr string) uint64 {
size := cast.ToFloat64(sizeStr)
return safeMul(size, multiplier)
}
// FloatOrDefault reads a configuration value
// from c by name and casts it to float64.
//
// Returns defaultValue if the value can not be casted.
func FloatOrDefault(c *Config, name string, defaultValue float64) float64 {
v, err := cast.ToFloat64E(c.Value(name))
if err != nil {
return defaultValue
}
return v
}

View file

@ -84,6 +84,8 @@ func TestEngineSection(t *testing.T) {
require.Equal(t, true, sc.Compress())
require.Equal(t, []string{"audio/*", "video/*"}, sc.UncompressableContentTypes())
require.Equal(t, true, sc.EstimateCompressibility())
require.Equal(t, float64(0.7), sc.EstimateCompressibilityThreshold())
require.EqualValues(t, 102400, sc.SmallSizeLimit())
require.Equal(t, 2, len(ss))

View file

@ -16,8 +16,11 @@ import (
// which provides access to Shard configurations.
type Config config.Config
const (
// SmallSizeLimitDefault is a default limit of small objects payload in bytes.
const SmallSizeLimitDefault = 1 << 20
SmallSizeLimitDefault = 1 << 20
EstimateCompressibilityThresholdDefault = 0.1
)
// From wraps config section into Config.
func From(c *config.Config) *Config {
@ -43,6 +46,30 @@ func (x *Config) UncompressableContentTypes() []string {
"compression_exclude_content_types")
}
// EstimateCompressibility returns the value of "estimate_compressibility" config parameter.
//
// Returns false if the value is not a valid bool.
func (x *Config) EstimateCompressibility() bool {
return config.BoolSafe(
(*config.Config)(x),
"compression_estimate_compressibility",
)
}
// EstimateCompressibilityThreshold returns the value of "estimate_compressibility_threshold" config parameter.
//
// Returns EstimateCompressibilityThresholdDefault if the value is not defined, not valid float or not in range [0.0; 1.0].
func (x *Config) EstimateCompressibilityThreshold() float64 {
v := config.FloatOrDefault(
(*config.Config)(x),
"compression_estimate_compressibility_threshold",
EstimateCompressibilityThresholdDefault)
if v < 0.0 || v > 1.0 {
return EstimateCompressibilityThresholdDefault
}
return v
}
// SmallSizeLimit returns the value of "small_object_size" config parameter.
//
// Returns SmallSizeLimitDefault if the value is not a positive number.

View file

@ -113,6 +113,8 @@ FROSTFS_STORAGE_SHARD_0_METABASE_MAX_BATCH_DELAY=10ms
### Blobstor config
FROSTFS_STORAGE_SHARD_0_COMPRESS=true
FROSTFS_STORAGE_SHARD_0_COMPRESSION_EXCLUDE_CONTENT_TYPES="audio/* video/*"
FROSTFS_STORAGE_SHARD_0_COMPRESSION_ESTIMATE_COMPRESSIBILITY=true
FROSTFS_STORAGE_SHARD_0_COMPRESSION_ESTIMATE_COMPRESSIBILITY_THRESHOLD=0.7
FROSTFS_STORAGE_SHARD_0_SMALL_OBJECT_SIZE=102400
### Blobovnicza config
FROSTFS_STORAGE_SHARD_0_BLOBSTOR_0_PATH=tmp/0/blob/blobovnicza

View file

@ -160,6 +160,8 @@
"compression_exclude_content_types": [
"audio/*", "video/*"
],
"compression_estimate_compressibility": true,
"compression_estimate_compressibility_threshold": 0.7,
"small_object_size": 102400,
"blobstor": [
{

View file

@ -178,6 +178,8 @@ storage:
compression_exclude_content_types:
- audio/*
- video/*
compression_estimate_compressibility: true
compression_estimate_compressibility_threshold: 0.7
blobstor:
- type: blobovnicza

View file

@ -181,6 +181,8 @@ The following table describes configuration for each shard.
|-------------------------------------|---------------------------------------------|---------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `compress` | `bool` | `false` | Flag to enable compression. |
| `compression_exclude_content_types` | `[]string` | | List of content-types to disable compression for. Content-type is taken from `Content-Type` object attribute. Each element can contain a star `*` as a first (last) character, which matches any prefix (suffix). |
| `compression_estimate_compressibility` | `bool` | `false` | If `true`, then noramalized compressibility estimation is used to decide compress data or not. |
| `compression_estimate_compressibility_threshold` | `float` | `0.1` | Normilized compressibility estimate threshold: data will compress if estimation if greater than this value. |
| `mode` | `string` | `read-write` | Shard Mode.<br/>Possible values: `read-write`, `read-only`, `degraded`, `degraded-read-only`, `disabled` |
| `resync_metabase` | `bool` | `false` | Flag to enable metabase resync on start. |
| `writecache` | [Writecache config](#writecache-subsection) | | Write-cache configuration. |

View file

@ -107,6 +107,27 @@ func WithCompressObjects(comp bool) Option {
}
}
// WithCompressibilityEstimate returns an option to use
// normilized compressibility estimate to decide compress
// data or not.
//
// See https://github.com/klauspost/compress/blob/v1.17.2/compressible.go#L5
func WithCompressibilityEstimate(v bool) Option {
return func(c *cfg) {
c.compression.UseCompressEstimation = v
}
}
// WithCompressibilityEstimateThreshold returns an option to set
// normilized compressibility estimate threshold.
//
// See https://github.com/klauspost/compress/blob/v1.17.2/compressible.go#L5
func WithCompressibilityEstimateThreshold(threshold float64) Option {
return func(c *cfg) {
c.compression.CompressEstimationThreshold = threshold
}
}
// WithUncompressableContentTypes returns option to disable decompression
// for specific content types as seen by object.AttributeContentType attribute.
func WithUncompressableContentTypes(values []string) Option {

View file

@ -3,8 +3,10 @@ package compression
import (
"crypto/rand"
"fmt"
"log"
"testing"
"github.com/klauspost/compress"
"github.com/stretchr/testify/require"
)
@ -47,3 +49,50 @@ func notSoRandomSlice(size, blockSize int) []byte {
}
return data
}
func BenchmarkCompressionRealVSEstimate(b *testing.B) {
var total float64 // to prevent from compiler optimizations
maxSize := 60 * 1024 * 1024
b.Run("estimate", func(b *testing.B) {
b.ResetTimer()
c := &Config{
Enabled: true,
}
require.NoError(b, c.Init())
for size := 1024; size <= maxSize; size *= 2 {
data := make([]byte, size)
_, err := rand.Reader.Read(data)
require.NoError(b, err)
b.StartTimer()
estimation := compress.Estimate(data)
total += estimation
b.StopTimer()
}
})
b.Run("compress", func(b *testing.B) {
b.ResetTimer()
c := &Config{
Enabled: true,
}
require.NoError(b, c.Init())
for size := 1024; size <= maxSize; size *= 2 {
data := make([]byte, size)
_, err := rand.Reader.Read(data)
require.NoError(b, err)
b.StartTimer()
maxSize := c.encoder.MaxEncodedSize(len(data))
compressed := c.encoder.EncodeAll(data, make([]byte, 0, maxSize))
total += float64(len(compressed)) / float64(len(data))
b.StopTimer()
}
})
log.Println(total)
}

View file

@ -5,6 +5,7 @@ import (
"strings"
objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
"github.com/klauspost/compress"
"github.com/klauspost/compress/zstd"
)
@ -13,6 +14,9 @@ type Config struct {
Enabled bool
UncompressableContentTypes []string
UseCompressEstimation bool
CompressEstimationThreshold float64
encoder *zstd.Encoder
decoder *zstd.Decoder
}
@ -82,6 +86,17 @@ func (c *Config) Compress(data []byte) []byte {
if c == nil || !c.Enabled {
return data
}
if c.UseCompressEstimation {
estimated := compress.Estimate(data)
if estimated >= c.CompressEstimationThreshold {
return c.compress(data)
}
return data
}
return c.compress(data)
}
func (c *Config) compress(data []byte) []byte {
maxSize := c.encoder.MaxEncodedSize(len(data))
compressed := c.encoder.EncodeAll(data, make([]byte, 0, maxSize))
if len(data) < len(compressed) {