frostfs-node/pkg/local_object_storage/writecache/mode.go
2024-12-18 15:52:26 +00:00

128 lines
3.1 KiB
Go

package writecache
import (
"context"
"errors"
"fmt"
"os"
"time"
"git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/blobstor/common"
"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard/mode"
"git.frostfs.info/TrueCloudLab/frostfs-observability/tracing"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/trace"
)
type setModePrm struct {
ignoreErrors bool
shrink bool
}
// 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(ctx context.Context, m mode.Mode) error {
ctx, span := tracing.StartSpanFromContext(ctx, "writecache.SetMode",
trace.WithAttributes(
attribute.String("mode", m.String()),
))
defer span.End()
c.modeMtx.Lock()
defer c.modeMtx.Unlock()
err := c.setMode(ctx, m, setModePrm{ignoreErrors: true})
if err == nil {
c.metrics.SetMode(mode.ConvertToComponentModeDegraded(m))
}
return err
}
// setMode applies new mode. Must be called with cache.modeMtx lock taken.
func (c *cache) setMode(ctx context.Context, m mode.Mode, prm setModePrm) error {
var err error
turnOffMeta := m.NoMetabase()
if turnOffMeta && !c.mode.NoMetabase() {
err = c.flush(ctx, prm.ignoreErrors)
if err != nil {
return err
}
}
if err := c.closeStorage(ctx, prm.shrink); err != nil {
return err
}
// Suspend producers to ensure there are channel send operations in fly.
// flushCh is populated by `flush` with `modeMtx` taken, thus waiting until it is empty
// guarantees that there are no in-fly operations.
for len(c.flushCh) != 0 {
c.log.Info(ctx, logs.WritecacheWaitingForChannelsToFlush)
time.Sleep(time.Second)
}
if turnOffMeta {
c.mode = m
return nil
}
if err = c.openStore(mode.ConvertToComponentModeDegraded(m)); err != nil {
return err
}
c.mode = m
return nil
}
func (c *cache) closeStorage(ctx context.Context, shrink bool) error {
if c.fsTree == nil {
return nil
}
if !shrink {
if err := c.fsTree.Close(ctx); err != nil {
return fmt.Errorf("close write-cache storage: %w", err)
}
return nil
}
empty := true
_, err := c.fsTree.Iterate(ctx, common.IteratePrm{
Handler: func(common.IterationElement) error {
return errIterationCompleted
},
})
if err != nil {
if errors.Is(err, errIterationCompleted) {
empty = false
} else {
return fmt.Errorf("check write-cache items: %w", err)
}
}
if err := c.fsTree.Close(ctx); err != nil {
return fmt.Errorf("close write-cache storage: %w", err)
}
if empty {
err := os.RemoveAll(c.path)
if err != nil && !os.IsNotExist(err) {
return fmt.Errorf("remove write-cache files: %w", err)
}
} else {
c.log.Info(ctx, logs.WritecacheShrinkSkippedNotEmpty)
}
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()
}
// noMetabase returns true if c is operating without the metabase.
// `c.modeMtx` must be taken.
func (c *cache) noMetabase() bool {
return c.mode.NoMetabase()
}