frostfs-node/pkg/local_object_storage/writecache/writecache.go
Evgenii Stratonikov 3711976dfc [#314] writecache: remove objects right after they are flushed
Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
2023-05-16 14:16:25 +03:00

173 lines
4.3 KiB
Go

package writecache
import (
"context"
"os"
"sync"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/fstree"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard/mode"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/util/logger"
"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
"go.etcd.io/bbolt"
"go.uber.org/zap"
)
// Info groups the information about write-cache.
type Info struct {
// Full path to the write-cache.
Path string
}
// Cache represents write-cache for objects.
type Cache interface {
Get(ctx context.Context, address oid.Address) (*object.Object, error)
Head(context.Context, oid.Address) (*object.Object, error)
// Delete removes object referenced by the given oid.Address from the
// Cache. Returns any error encountered that prevented the object to be
// removed.
//
// Returns apistatus.ObjectNotFound if object is missing in the Cache.
// Returns ErrReadOnly if the Cache is currently in the read-only mode.
Delete(oid.Address) error
Iterate(IterationPrm) error
Put(common.PutPrm) (common.PutRes, error)
SetMode(mode.Mode) error
SetLogger(*logger.Logger)
DumpInfo() Info
Flush(bool) error
Init() error
Open(readOnly bool) error
Close() error
}
type cache struct {
options
// mtx protects statistics, counters and compressFlags.
mtx sync.RWMutex
mode mode.Mode
modeMtx sync.RWMutex
// compressFlags maps address of a big object to boolean value indicating
// whether object should be compressed.
compressFlags map[string]struct{}
// flushCh is a channel with objects to flush.
flushCh chan *object.Object
// closeCh is close channel, protected by modeMtx.
closeCh chan struct{}
// wg is a wait group for flush workers.
wg sync.WaitGroup
// store contains underlying database.
store
// fsTree contains big files stored directly on file-system.
fsTree *fstree.FSTree
}
// wcStorageType is used for write-cache operations logging.
const wcStorageType = "write-cache"
type objectInfo struct {
addr string
data []byte
obj *object.Object
}
const (
defaultMaxObjectSize = 64 * 1024 * 1024 // 64 MiB
defaultSmallObjectSize = 32 * 1024 // 32 KiB
defaultMaxCacheSize = 1 << 30 // 1 GiB
)
var (
defaultBucket = []byte{0}
)
// New creates new writecache instance.
func New(opts ...Option) Cache {
c := &cache{
flushCh: make(chan *object.Object),
mode: mode.ReadWrite,
compressFlags: make(map[string]struct{}),
options: options{
log: &logger.Logger{Logger: zap.NewNop()},
maxObjectSize: defaultMaxObjectSize,
smallObjectSize: defaultSmallObjectSize,
workersCount: defaultFlushWorkersCount,
maxCacheSize: defaultMaxCacheSize,
maxBatchSize: bbolt.DefaultMaxBatchSize,
maxBatchDelay: bbolt.DefaultMaxBatchDelay,
openFile: os.OpenFile,
},
}
for i := range opts {
opts[i](&c.options)
}
return c
}
// SetLogger sets logger. It is used after the shard ID was generated to use it in logs.
func (c *cache) SetLogger(l *logger.Logger) {
c.log = l
}
func (c *cache) DumpInfo() Info {
return Info{
Path: c.path,
}
}
// Open opens and initializes database. Reads object counters from the ObjectCounters instance.
func (c *cache) Open(readOnly bool) error {
err := c.openStore(readOnly)
if err != nil {
return err
}
// Opening after Close is done during maintenance mode,
// thus we need to create a channel here.
c.closeCh = make(chan struct{})
return c.initCounters()
}
// Init runs necessary services.
func (c *cache) Init() error {
c.runFlushLoop()
return nil
}
// Close closes db connection and stops services. Executes ObjectCounters.FlushAndClose op.
func (c *cache) Close() error {
// We cannot lock mutex for the whole operation duration
// because it is taken by some background workers, so `wg.Wait()` is done without modeMtx.
c.modeMtx.Lock()
if c.closeCh != nil {
close(c.closeCh)
}
c.mode = mode.DegradedReadOnly // prevent new operations from being processed
c.modeMtx.Unlock()
c.wg.Wait()
c.modeMtx.Lock()
defer c.modeMtx.Unlock()
c.closeCh = nil
var err error
if c.db != nil {
err = c.db.Close()
if err != nil {
c.db = nil
}
}
return nil
}