frostfs-node/pkg/local_object_storage/writecache/flush.go
Evgenii Stratonikov 9eb018672c [#1523] blobstor: Unify parameters for Put operation
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-08-22 13:14:19 +03:00

257 lines
5.3 KiB
Go

package writecache
import (
"sync"
"time"
"github.com/mr-tron/base58"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobovnicza"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/common"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase"
"github.com/nspcc-dev/neofs-sdk-go/object"
oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
"go.etcd.io/bbolt"
"go.uber.org/zap"
)
const (
// flushBatchSize is amount of keys which will be read from cache to be flushed
// to the main storage. It is used to reduce contention between cache put
// and cache persist.
flushBatchSize = 512
// defaultFlushWorkersCount is number of workers for putting objects in main storage.
defaultFlushWorkersCount = 20
// defaultFlushInterval is default time interval between successive flushes.
defaultFlushInterval = time.Second
)
// flushLoop periodically flushes changes from the database to memory.
func (c *cache) flushLoop() {
var wg sync.WaitGroup
for i := 0; i < c.workersCount; i++ {
wg.Add(1)
go func(i int) {
defer wg.Done()
c.flushWorker(i)
}(i)
}
wg.Add(1)
go func() {
defer wg.Done()
c.flushBigObjects()
}()
tt := time.NewTimer(defaultFlushInterval)
defer tt.Stop()
for {
select {
case <-tt.C:
c.flush()
tt.Reset(defaultFlushInterval)
case <-c.closeCh:
c.log.Debug("waiting for workers to quit")
wg.Wait()
return
}
}
}
func (c *cache) flush() {
lastKey := []byte{}
var m []objectInfo
for {
m = m[:0]
sz := 0
c.modeMtx.RLock()
if c.readOnly() {
c.modeMtx.RUnlock()
time.Sleep(time.Second)
continue
}
// We put objects in batches of fixed size to not interfere with main put cycle a lot.
_ = c.db.View(func(tx *bbolt.Tx) error {
b := tx.Bucket(defaultBucket)
cs := b.Cursor()
for k, v := cs.Seek(lastKey); k != nil && len(m) < flushBatchSize; k, v = cs.Next() {
if _, ok := c.flushed.Peek(string(k)); ok {
continue
}
sz += len(k) + len(v)
m = append(m, objectInfo{
addr: string(k),
data: cloneBytes(v),
})
}
return nil
})
for i := range m {
obj := object.New()
if err := obj.Unmarshal(m[i].data); err != nil {
continue
}
select {
case c.flushCh <- obj:
case <-c.closeCh:
c.modeMtx.RUnlock()
return
}
}
if len(m) == 0 {
c.modeMtx.RUnlock()
break
}
c.evictObjects(len(m))
for i := range m {
c.flushed.Add(m[i].addr, true)
}
c.modeMtx.RUnlock()
c.log.Debug("flushed items from write-cache",
zap.Int("count", len(m)),
zap.String("start", base58.Encode(lastKey)))
}
}
func (c *cache) flushBigObjects() {
tick := time.NewTicker(defaultFlushInterval * 10)
for {
select {
case <-tick.C:
c.modeMtx.RLock()
if c.readOnly() {
c.modeMtx.RUnlock()
break
}
evictNum := 0
var prm fstree.IterationPrm
prm.WithLazyHandler(func(addr oid.Address, f func() ([]byte, error)) error {
sAddr := addr.EncodeToString()
if _, ok := c.store.flushed.Peek(sAddr); ok {
return nil
}
data, err := f()
if err != nil {
c.log.Error("can't read a file", zap.Stringer("address", addr))
return nil
}
c.mtx.Lock()
_, compress := c.compressFlags[sAddr]
c.mtx.Unlock()
var prm common.PutPrm
prm.Address = addr
prm.RawData = data
if _, err := c.blobstor.PutRaw(common.PutPrm{Address: addr, RawData: data}, compress); err != nil {
c.log.Error("cant flush object to blobstor", zap.Error(err))
return nil
}
if compress {
c.mtx.Lock()
delete(c.compressFlags, sAddr)
c.mtx.Unlock()
}
// mark object as flushed
c.store.flushed.Add(sAddr, false)
evictNum++
return nil
})
_ = c.fsTree.Iterate(prm)
// evict objects which were successfully written to BlobStor
c.evictObjects(evictNum)
c.modeMtx.RUnlock()
case <-c.closeCh:
}
}
}
// flushWorker runs in a separate goroutine and write objects to the main storage.
// If flushFirst is true, flushing objects from cache database takes priority over
// putting new objects.
func (c *cache) flushWorker(num int) {
priorityCh := c.directCh
switch num % 3 {
case 0:
priorityCh = c.flushCh
case 1:
priorityCh = c.metaCh
}
var obj *object.Object
for {
metaOnly := false
// Give priority to direct put.
// TODO(fyrchik): #1150 do this once in N iterations depending on load
select {
case obj = <-priorityCh:
metaOnly = num%3 == 1
default:
select {
case obj = <-c.directCh:
case obj = <-c.flushCh:
case obj = <-c.metaCh:
metaOnly = true
case <-c.closeCh:
return
}
}
err := c.writeObject(obj, metaOnly)
if err != nil {
c.log.Error("can't flush object to the main storage", zap.Error(err))
}
}
}
// writeObject is used to write object directly to the main storage.
func (c *cache) writeObject(obj *object.Object, metaOnly bool) error {
var id *blobovnicza.ID
if !metaOnly {
var prm common.PutPrm
prm.Object = obj
res, err := c.blobstor.Put(prm)
if err != nil {
return err
}
id = res.BlobovniczaID
}
var pPrm meta.PutPrm
pPrm.SetObject(obj)
pPrm.SetBlobovniczaID(id)
_, err := c.metabase.Put(pPrm)
return err
}
func cloneBytes(a []byte) []byte {
b := make([]byte, len(a))
copy(b, a)
return b
}