Files
seaweedFS/weed/storage/store_ec.go
Chris Lu e10f11b480 opt: reduce ShardsInfo memory usage with bitmap and sorted slice (#7974)
* opt: reduce ShardsInfo memory usage with bitmap and sorted slice

- Replace map[ShardId]*ShardInfo with sorted []ShardInfo slice
- Add ShardBits (uint32) bitmap for O(1) existence checks
- Use binary search for O(log n) lookups by shard ID
- Maintain sorted order for efficient iteration
- Add comprehensive unit tests and benchmarks

Memory savings:
- Map overhead: ~48 bytes per entry eliminated
- Pointers: 8 bytes per entry eliminated
- Total: ~56 bytes per shard saved

Performance improvements:
- Has(): O(1) using bitmap
- Size(): O(log n) using binary search (was O(1), acceptable tradeoff)
- Count(): O(1) using popcount on bitmap
- Iteration: Faster due to cache locality

* refactor: add methods to ShardBits type

- Add Has(), Set(), Clear(), and Count() methods to ShardBits
- Simplify ShardsInfo methods by using ShardBits methods
- Improves code readability and encapsulation

* opt: use ShardBits directly in ShardsCountFromVolumeEcShardInformationMessage

Avoid creating a full ShardsInfo object just to count shards.
Directly cast vi.EcIndexBits to ShardBits and use Count() method.

* opt: use strings.Builder in ShardsInfo.String() for efficiency

* refactor: change AsSlice to return []ShardInfo (values instead of pointers)

This completes the memory optimization by avoiding unnecessary pointer slices and potential allocations.

* refactor: rename ShardsCountFromVolumeEcShardInformationMessage to GetShardCount

* fix: prevent deadlock in Add and Subtract methods

Copy shards data from 'other' before releasing its lock to avoid
potential deadlock when a.Add(b) and b.Add(a) are called concurrently.

The previous implementation held other's lock while calling si.Set/Delete,
which acquires si's lock. This could deadlock if two goroutines tried to
add/subtract each other concurrently.

* opt: avoid unnecessary locking in constructor functions

ShardsInfoFromVolume and ShardsInfoFromVolumeEcShardInformationMessage
now build shards slice and bitmap directly without calling Set(), which
acquires a lock on every call. Since the object is local and not yet
shared, locking is unnecessary and adds overhead.

This improves performance during object construction.

* fix: rename 'copy' variable to avoid shadowing built-in function

The variable name 'copy' in TestShardsInfo_Copy shadowed the built-in
copy() function, which is confusing and bad practice. Renamed to 'siCopy'.

* opt: use math/bits.OnesCount32 and reorganize types

1. Replace manual popcount loop with math/bits.OnesCount32 for better
   performance and idiomatic Go code
2. Move ShardSize type definition to ec_shards_info.go for better code
   organization since it's primarily used there

* refactor: Set() now accepts ShardInfo for future extensibility

Changed Set(id ShardId, size ShardSize) to Set(shard ShardInfo) to
support future additions to ShardInfo without changing the API.

This makes the code more extensible as new fields can be added to
ShardInfo (e.g., checksum, location, etc.) without breaking the Set API.

* refactor: move ShardInfo and ShardSize to separate file

Created ec_shard_info.go to hold the basic shard types (ShardInfo and
ShardSize) for better code organization and separation of concerns.

* refactor: add ShardInfo constructor and helper functions

Added NewShardInfo() constructor and IsValid() method to better
encapsulate ShardInfo creation and validation. Updated code to use
the constructor for cleaner, more maintainable code.

* fix: update remaining Set() calls to use NewShardInfo constructor

Fixed compilation errors in storage and shell packages where Set() calls
were not updated to use the new NewShardInfo() constructor.

* fix: remove unreachable code in filer backup commands

Removed unreachable return statements after infinite loops in
filer_backup.go and filer_meta_backup.go to fix compilation errors.

* fix: rename 'new' variable to avoid shadowing built-in

Renamed 'new' to 'result' in MinusParityShards, Plus, and Minus methods
to avoid shadowing Go's built-in new() function.

* fix: update remaining test files to use NewShardInfo constructor

Fixed Set() calls in command_volume_list_test.go and
ec_rebalance_slots_test.go to use NewShardInfo() constructor.
2026-01-06 00:09:52 -08:00

417 lines
14 KiB
Go

package storage
import (
"context"
"fmt"
"io"
"os"
"slices"
"sync"
"time"
"github.com/klauspost/reedsolomon"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/operation"
"github.com/seaweedfs/seaweedfs/weed/pb"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/pb/volume_server_pb"
"github.com/seaweedfs/seaweedfs/weed/stats"
"github.com/seaweedfs/seaweedfs/weed/storage/erasure_coding"
"github.com/seaweedfs/seaweedfs/weed/storage/needle"
"github.com/seaweedfs/seaweedfs/weed/storage/types"
)
func (s *Store) CollectErasureCodingHeartbeat() *master_pb.Heartbeat {
var ecShardMessages []*master_pb.VolumeEcShardInformationMessage
collectionEcShardSize := make(map[string]int64)
for diskId, location := range s.Locations {
location.ecVolumesLock.RLock()
for _, ecShards := range location.ecVolumes {
ecShardMessages = append(ecShardMessages, ecShards.ToVolumeEcShardInformationMessage(uint32(diskId))...)
for _, ecShard := range ecShards.Shards {
collectionEcShardSize[ecShards.Collection] += ecShard.Size()
}
}
location.ecVolumesLock.RUnlock()
}
for col, size := range collectionEcShardSize {
stats.VolumeServerDiskSizeGauge.WithLabelValues(col, "ec").Set(float64(size))
}
return &master_pb.Heartbeat{
EcShards: ecShardMessages,
HasNoEcShards: len(ecShardMessages) == 0,
}
}
func (s *Store) MountEcShards(collection string, vid needle.VolumeId, shardId erasure_coding.ShardId) error {
for diskId, location := range s.Locations {
if ecVolume, err := location.LoadEcShard(collection, vid, shardId); err == nil {
glog.V(0).Infof("MountEcShards %d.%d on disk ID %d", vid, shardId, diskId)
si := erasure_coding.NewShardsInfo()
si.Set(erasure_coding.NewShardInfo(shardId, erasure_coding.ShardSize(ecVolume.ShardSize())))
s.NewEcShardsChan <- master_pb.VolumeEcShardInformationMessage{
Id: uint32(vid),
Collection: collection,
EcIndexBits: uint32(si.Bitmap()),
ShardSizes: si.SizesInt64(),
DiskType: string(location.DiskType),
ExpireAtSec: ecVolume.ExpireAtSec,
DiskId: uint32(diskId),
}
return nil
} else if err == os.ErrNotExist {
continue
} else {
return fmt.Errorf("%s load ec shard %d.%d: %v", location.Directory, vid, shardId, err)
}
}
return fmt.Errorf("MountEcShards %d.%d not found on disk", vid, shardId)
}
func (s *Store) UnmountEcShards(vid needle.VolumeId, shardId erasure_coding.ShardId) error {
diskId, ecShard, found := s.findEcShard(vid, shardId)
if !found {
return nil
}
si := erasure_coding.NewShardsInfo()
si.Set(erasure_coding.NewShardInfo(shardId, 0))
message := master_pb.VolumeEcShardInformationMessage{
Id: uint32(vid),
Collection: ecShard.Collection,
EcIndexBits: si.Bitmap(),
ShardSizes: si.SizesInt64(),
DiskType: string(ecShard.DiskType),
DiskId: diskId,
}
location := s.Locations[diskId]
if deleted := location.UnloadEcShard(vid, shardId); deleted {
glog.V(0).Infof("UnmountEcShards %d.%d", vid, shardId)
s.DeletedEcShardsChan <- message
return nil
}
return fmt.Errorf("UnmountEcShards %d.%d not found on disk", vid, shardId)
}
func (s *Store) findEcShard(vid needle.VolumeId, shardId erasure_coding.ShardId) (diskId uint32, shard *erasure_coding.EcVolumeShard, found bool) {
for diskId, location := range s.Locations {
if v, found := location.FindEcShard(vid, shardId); found {
return uint32(diskId), v, found
}
}
return 0, nil, false
}
func (s *Store) FindEcVolume(vid needle.VolumeId) (*erasure_coding.EcVolume, bool) {
for _, location := range s.Locations {
if s, found := location.FindEcVolume(vid); found {
return s, true
}
}
return nil, false
}
// shardFiles is a list of shard files, which is used to return the shard locations
func (s *Store) CollectEcShards(vid needle.VolumeId, shardFileNames []string) (ecVolume *erasure_coding.EcVolume, found bool) {
for _, location := range s.Locations {
if s, foundShards := location.CollectEcShards(vid, shardFileNames); foundShards {
ecVolume = s
found = true
}
}
return
}
func (s *Store) DestroyEcVolume(vid needle.VolumeId) {
for _, location := range s.Locations {
location.DestroyEcVolume(vid)
}
}
func (s *Store) ReadEcShardNeedle(vid needle.VolumeId, n *needle.Needle, onReadSizeFn func(size types.Size)) (int, error) {
for _, location := range s.Locations {
if localEcVolume, found := location.FindEcVolume(vid); found {
offset, size, intervals, err := localEcVolume.LocateEcShardNeedle(n.Id, localEcVolume.Version)
if err != nil {
return 0, fmt.Errorf("locate in local ec volume: %w", err)
}
if size.IsDeleted() {
return 0, ErrorDeleted
}
if onReadSizeFn != nil {
onReadSizeFn(size)
}
glog.V(3).Infof("read ec volume %d offset %d size %d intervals:%+v", vid, offset.ToActualOffset(), size, intervals)
if len(intervals) > 1 {
glog.V(3).Infof("ReadEcShardNeedle needle id %s intervals:%+v", n.String(), intervals)
}
bytes, isDeleted, err := s.readEcShardIntervals(vid, n.Id, localEcVolume, intervals)
if err != nil {
return 0, fmt.Errorf("ReadEcShardIntervals: %w", err)
}
if isDeleted {
return 0, ErrorDeleted
}
err = n.ReadBytes(bytes, offset.ToActualOffset(), size, localEcVolume.Version)
if err != nil {
return 0, fmt.Errorf("readbytes: %w", err)
}
return len(bytes), nil
}
}
return 0, fmt.Errorf("ec shard %d not found", vid)
}
func (s *Store) readEcShardIntervals(vid needle.VolumeId, needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, intervals []erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
if err = s.cachedLookupEcShardLocations(ecVolume); err != nil {
return nil, false, fmt.Errorf("failed to locate shard via master grpc %s: %v", s.MasterAddress, err)
}
for i, interval := range intervals {
if d, isDeleted, e := s.readOneEcShardInterval(needleId, ecVolume, interval); e != nil {
return nil, isDeleted, e
} else {
if isDeleted {
is_deleted = true
}
if i == 0 {
data = d
} else {
data = append(data, d...)
}
}
}
return
}
func (s *Store) readOneEcShardInterval(needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, interval erasure_coding.Interval) (data []byte, is_deleted bool, err error) {
shardId, actualOffset := interval.ToShardIdAndOffset(erasure_coding.ErasureCodingLargeBlockSize, erasure_coding.ErasureCodingSmallBlockSize)
data = make([]byte, interval.Size)
if shard, found := ecVolume.FindEcVolumeShard(shardId); found {
var readSize int
if readSize, err = shard.ReadAt(data, actualOffset); err != nil {
if readSize != int(interval.Size) {
glog.V(0).Infof("read local ec shard %d.%d offset %d: %v", ecVolume.VolumeId, shardId, actualOffset, err)
return
}
}
} else {
ecVolume.ShardLocationsLock.RLock()
sourceDataNodes, hasShardIdLocation := ecVolume.ShardLocations[shardId]
ecVolume.ShardLocationsLock.RUnlock()
// try reading directly
if hasShardIdLocation {
_, is_deleted, err = s.readRemoteEcShardInterval(sourceDataNodes, needleId, ecVolume.VolumeId, shardId, data, actualOffset)
if err == nil {
return
}
glog.V(0).Infof("clearing ec shard %d.%d locations: %v", ecVolume.VolumeId, shardId, err)
}
// try reading by recovering from other shards
_, is_deleted, err = s.recoverOneRemoteEcShardInterval(needleId, ecVolume, shardId, data, actualOffset)
if err == nil {
return
}
glog.V(0).Infof("recover ec shard %d.%d : %v", ecVolume.VolumeId, shardId, err)
}
return
}
func forgetShardId(ecVolume *erasure_coding.EcVolume, shardId erasure_coding.ShardId) {
// failed to access the source data nodes, clear it up
ecVolume.ShardLocationsLock.Lock()
delete(ecVolume.ShardLocations, shardId)
ecVolume.ShardLocationsLock.Unlock()
}
func (s *Store) cachedLookupEcShardLocations(ecVolume *erasure_coding.EcVolume) (err error) {
shardCount := len(ecVolume.ShardLocations)
if shardCount < erasure_coding.DataShardsCount &&
ecVolume.ShardLocationsRefreshTime.Add(11*time.Second).After(time.Now()) ||
shardCount == erasure_coding.TotalShardsCount &&
ecVolume.ShardLocationsRefreshTime.Add(37*time.Minute).After(time.Now()) ||
shardCount >= erasure_coding.DataShardsCount &&
ecVolume.ShardLocationsRefreshTime.Add(7*time.Minute).After(time.Now()) {
// still fresh
return nil
}
glog.V(3).Infof("lookup and cache ec volume %d locations", ecVolume.VolumeId)
err = operation.WithMasterServerClient(false, s.MasterAddress, s.grpcDialOption, func(masterClient master_pb.SeaweedClient) error {
req := &master_pb.LookupEcVolumeRequest{
VolumeId: uint32(ecVolume.VolumeId),
}
resp, err := masterClient.LookupEcVolume(context.Background(), req)
if err != nil {
return fmt.Errorf("lookup ec volume %d: %v", ecVolume.VolumeId, err)
}
if len(resp.ShardIdLocations) < erasure_coding.DataShardsCount {
return fmt.Errorf("only %d shards found but %d required", len(resp.ShardIdLocations), erasure_coding.DataShardsCount)
}
ecVolume.ShardLocationsLock.Lock()
for _, shardIdLocations := range resp.ShardIdLocations {
shardId := erasure_coding.ShardId(shardIdLocations.ShardId)
delete(ecVolume.ShardLocations, shardId)
for _, loc := range shardIdLocations.Locations {
ecVolume.ShardLocations[shardId] = append(ecVolume.ShardLocations[shardId], pb.NewServerAddressFromLocation(loc))
}
}
ecVolume.ShardLocationsRefreshTime = time.Now()
ecVolume.ShardLocationsLock.Unlock()
return nil
})
return
}
func (s *Store) readRemoteEcShardInterval(sourceDataNodes []pb.ServerAddress, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
if len(sourceDataNodes) == 0 {
return 0, false, fmt.Errorf("failed to find ec shard %d.%d", vid, shardId)
}
for _, sourceDataNode := range sourceDataNodes {
glog.V(3).Infof("read remote ec shard %d.%d from %s", vid, shardId, sourceDataNode)
n, is_deleted, err = s.doReadRemoteEcShardInterval(sourceDataNode, needleId, vid, shardId, buf, offset)
if err == nil {
return
}
glog.V(1).Infof("read remote ec shard %d.%d from %s: %v", vid, shardId, sourceDataNode, err)
}
return
}
func (s *Store) doReadRemoteEcShardInterval(sourceDataNode pb.ServerAddress, needleId types.NeedleId, vid needle.VolumeId, shardId erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
err = operation.WithVolumeServerClient(false, sourceDataNode, s.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error {
// copy data slice
shardReadClient, err := client.VolumeEcShardRead(context.Background(), &volume_server_pb.VolumeEcShardReadRequest{
VolumeId: uint32(vid),
ShardId: uint32(shardId),
Offset: offset,
Size: int64(len(buf)),
FileKey: uint64(needleId),
})
if err != nil {
return fmt.Errorf("failed to start reading ec shard %d.%d from %s: %v", vid, shardId, sourceDataNode, err)
}
for {
resp, receiveErr := shardReadClient.Recv()
if receiveErr == io.EOF {
break
}
if receiveErr != nil {
return fmt.Errorf("receiving ec shard %d.%d from %s: %v", vid, shardId, sourceDataNode, receiveErr)
}
if resp.IsDeleted {
is_deleted = true
}
copy(buf[n:n+len(resp.Data)], resp.Data)
n += len(resp.Data)
}
return nil
})
if err != nil {
return 0, is_deleted, fmt.Errorf("read ec shard %d.%d from %s: %v", vid, shardId, sourceDataNode, err)
}
return
}
func (s *Store) recoverOneRemoteEcShardInterval(needleId types.NeedleId, ecVolume *erasure_coding.EcVolume, shardIdToRecover erasure_coding.ShardId, buf []byte, offset int64) (n int, is_deleted bool, err error) {
glog.V(3).Infof("recover ec shard %d.%d from other locations", ecVolume.VolumeId, shardIdToRecover)
enc, err := reedsolomon.New(erasure_coding.DataShardsCount, erasure_coding.ParityShardsCount)
if err != nil {
return 0, false, fmt.Errorf("failed to create encoder: %w", err)
}
// Use MaxShardCount to support custom EC ratios up to 32 shards
bufs := make([][]byte, erasure_coding.MaxShardCount)
var wg sync.WaitGroup
ecVolume.ShardLocationsLock.RLock()
for shardId, locations := range ecVolume.ShardLocations {
// skip current shard or empty shard
if shardId == shardIdToRecover {
continue
}
if len(locations) == 0 {
glog.V(3).Infof("readRemoteEcShardInterval missing %d.%d from %+v", ecVolume.VolumeId, shardId, locations)
continue
}
// read from remote locations
wg.Add(1)
go func(shardId erasure_coding.ShardId, locations []pb.ServerAddress) {
defer wg.Done()
data := make([]byte, len(buf))
nRead, isDeleted, readErr := s.readRemoteEcShardInterval(locations, needleId, ecVolume.VolumeId, shardId, data, offset)
if readErr != nil {
glog.V(3).Infof("recover: readRemoteEcShardInterval %d.%d %d bytes from %+v: %v", ecVolume.VolumeId, shardId, nRead, locations, readErr)
forgetShardId(ecVolume, shardId)
}
if isDeleted {
is_deleted = true
}
if nRead == len(buf) {
bufs[shardId] = data
}
}(shardId, locations)
}
ecVolume.ShardLocationsLock.RUnlock()
wg.Wait()
if err = enc.ReconstructData(bufs); err != nil {
glog.V(3).Infof("recovered ec shard %d.%d failed: %v", ecVolume.VolumeId, shardIdToRecover, err)
return 0, false, err
}
glog.V(4).Infof("recovered ec shard %d.%d from other locations", ecVolume.VolumeId, shardIdToRecover)
copy(buf, bufs[shardIdToRecover])
return len(buf), is_deleted, nil
}
func (s *Store) EcVolumes() (ecVolumes []*erasure_coding.EcVolume) {
for _, location := range s.Locations {
location.ecVolumesLock.RLock()
for _, v := range location.ecVolumes {
ecVolumes = append(ecVolumes, v)
}
location.ecVolumesLock.RUnlock()
}
slices.SortFunc(ecVolumes, func(a, b *erasure_coding.EcVolume) int {
return int(a.VolumeId) - int(b.VolumeId)
})
return ecVolumes
}