34544502dc
All checks were successful
ci/woodpecker/pr/pre-commit Pipeline was successful
Do not use write-cache as a read cache: always remove objects from the WC, not only if an object hasn't been used for some time (LRU cache is dropped). Use object size (in bytes) as a metric of used space, not an approximate (and too inaccurate) maximum stored objects number. Signed-off-by: Pavel Karpy <p.karpy@yadro.com>
100 lines
2.4 KiB
Go
100 lines
2.4 KiB
Go
package writecache
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"time"
|
|
|
|
"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/pkg/tracing"
|
|
"git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs"
|
|
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard/mode"
|
|
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/util/logicerr"
|
|
"go.opentelemetry.io/otel/attribute"
|
|
"go.opentelemetry.io/otel/trace"
|
|
)
|
|
|
|
// ErrReadOnly is returned when Put/Write is performed in a read-only mode.
|
|
var ErrReadOnly = logicerr.New("write-cache is in read-only mode")
|
|
|
|
// SetMode sets write-cache mode of operation.
|
|
// When shard is put in read-only mode all objects in memory are flushed to disk
|
|
// and all background jobs are suspended.
|
|
func (c *Cache) SetMode(m mode.Mode) error {
|
|
ctx, span := tracing.StartSpanFromContext(context.TODO(), "writecache.SetMode",
|
|
trace.WithAttributes(
|
|
attribute.String("mode", m.String()),
|
|
))
|
|
defer span.End()
|
|
|
|
return c.setMode(ctx, m)
|
|
}
|
|
|
|
// setMode applies new mode. Must be called with cache.modeMtx lock taken.
|
|
func (c *Cache) setMode(ctx context.Context, m mode.Mode) error {
|
|
var err error
|
|
|
|
c.modeMtx.Lock()
|
|
defer c.modeMtx.Unlock()
|
|
|
|
var workersActive bool
|
|
select {
|
|
case <-c.workersChan:
|
|
default:
|
|
workersActive = true
|
|
}
|
|
|
|
stopWorkers := m.NoMetabase() && !c.mode.NoMetabase() || c.mode.ReadWrite() && !m.ReadWrite()
|
|
if stopWorkers {
|
|
err = c.flush(ctx, true)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if workersActive {
|
|
close(c.workersChan)
|
|
c.wg.Wait()
|
|
}
|
|
}
|
|
|
|
if c.db != nil {
|
|
if err = c.db.Close(); err != nil {
|
|
return fmt.Errorf("can't close write-cache database: %w", err)
|
|
}
|
|
}
|
|
|
|
// Suspend producers to ensure there are channel send operations in fly.
|
|
// smallFlushCh is populated by `flush` with `modeMtx` taken, thus waiting until it is empty
|
|
// guarantees that there are no in-fly operations.
|
|
for len(c.smallFlushCh) != 0 {
|
|
c.log.Info(logs.WritecacheWaitingForChannelsToFlush)
|
|
time.Sleep(time.Second)
|
|
}
|
|
|
|
if m.NoMetabase() {
|
|
c.mode = m
|
|
return nil
|
|
}
|
|
|
|
if err = c.openStore(m.ReadOnly()); err != nil {
|
|
return err
|
|
}
|
|
|
|
c.mode = m
|
|
|
|
if m == mode.ReadWrite {
|
|
select {
|
|
case <-c.workersChan:
|
|
c.workersChan = make(chan struct{})
|
|
c.runFlushLoop()
|
|
default:
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// readOnly returns true if current mode is read-only.
|
|
// `c.modeMtx` must be taken.
|
|
func (c *Cache) readOnly() bool {
|
|
return c.mode.ReadOnly()
|
|
}
|