frostfs-node/pkg/local_object_storage/writecache/writecache.go
Evgenii Stratonikov 59de521fd1 [] blobstor: implement write-cache
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2021-04-29 17:36:36 +03:00

109 lines
2.5 KiB
Go

package writecache
import (
"sync"
objectSDK "github.com/nspcc-dev/neofs-api-go/pkg/object"
"github.com/nspcc-dev/neofs-node/pkg/core/object"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/fstree"
"go.uber.org/atomic"
"go.uber.org/zap"
)
// Cache represents write-cache for objects.
type Cache interface {
Get(*objectSDK.Address) (*object.Object, error)
Delete(*objectSDK.Address) error
Put(*object.Object) error
Init() error
Open() error
Close() error
}
type cache struct {
options
// mtx protects mem field, statistics and counters.
mtx sync.RWMutex
mem []objectInfo
// curMemSize is the current size of all objects cached in memory.
curMemSize uint64
// flushCh is a channel with objects to flush.
flushCh chan *object.Object
// directCh is a channel with objects to put directly to the main storage.
// it is prioritized over flushCh.
directCh chan *object.Object
// metaCh is a channel with objects for which only metadata needs to be written.
metaCh chan *object.Object
// closeCh is close channel.
closeCh chan struct{}
evictCh chan []byte
// store contains underlying database.
store
// dbSize stores approximate database size. It is updated every flush/persist cycle.
dbSize atomic.Uint64
// fsTree contains big files stored directly on file-system.
fsTree *fstree.FSTree
}
type objectInfo struct {
addr string
data []byte
obj *object.Object
}
const (
maxInMemorySizeBytes = 1024 * 1024 * 1024 // 1 GiB
maxObjectSize = 64 * 1024 * 1024 // 64 MiB
smallObjectSize = 32 * 1024 // 32 KiB
)
var (
defaultBucket = []byte{0}
)
// New creates new writecache instance.
func New(opts ...Option) Cache {
c := &cache{
flushCh: make(chan *object.Object),
directCh: make(chan *object.Object),
metaCh: make(chan *object.Object),
closeCh: make(chan struct{}),
evictCh: make(chan []byte),
options: options{
log: zap.NewNop(),
maxMemSize: maxInMemorySizeBytes,
maxObjectSize: maxObjectSize,
smallObjectSize: smallObjectSize,
workersCount: flushWorkersCount,
},
}
for i := range opts {
opts[i](&c.options)
}
return c
}
// Open opens and initializes database.
func (c *cache) Open() error {
return c.openStore()
}
// Init runs necessary services.
func (c *cache) Init() error {
go c.persistLoop()
go c.flushLoop()
return nil
}
// Close closes db connection and stops services.
func (c *cache) Close() error {
close(c.closeCh)
return c.db.Close()
}