frostfs-node/pkg/local_object_storage/engine/engine.go
Stanislav Bogatyrev cb016d53a6 [#1] Fix comments and error messages
Signed-off-by: Stanislav Bogatyrev <s.bogatyrev@yadro.com>
2023-02-06 17:41:14 +03:00

259 lines
5.7 KiB
Go

package engine
import (
"errors"
"sync"
"github.com/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard"
"github.com/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard/mode"
"github.com/TrueCloudLab/frostfs-node/pkg/local_object_storage/util/logicerr"
"github.com/TrueCloudLab/frostfs-node/pkg/util"
"github.com/TrueCloudLab/frostfs-node/pkg/util/logger"
"go.uber.org/atomic"
"go.uber.org/zap"
)
// StorageEngine represents FrostFS local storage engine.
type StorageEngine struct {
*cfg
mtx *sync.RWMutex
shards map[string]shardWrapper
shardPools map[string]util.WorkerPool
closeCh chan struct{}
setModeCh chan setModeRequest
wg sync.WaitGroup
blockExec struct {
mtx sync.RWMutex
err error
}
}
type shardWrapper struct {
errorCount *atomic.Uint32
*shard.Shard
}
type setModeRequest struct {
sh *shard.Shard
errorCount uint32
}
// setModeLoop listens setModeCh to perform degraded mode transition of a single shard.
// Instead of creating a worker per single shard we use a single goroutine.
func (e *StorageEngine) setModeLoop() {
defer e.wg.Done()
var (
mtx sync.RWMutex // protects inProgress map
inProgress = make(map[string]struct{})
)
for {
select {
case <-e.closeCh:
return
case r := <-e.setModeCh:
sid := r.sh.ID().String()
mtx.Lock()
_, ok := inProgress[sid]
if !ok {
inProgress[sid] = struct{}{}
go func() {
e.moveToDegraded(r.sh, r.errorCount)
mtx.Lock()
delete(inProgress, sid)
mtx.Unlock()
}()
}
mtx.Unlock()
}
}
}
func (e *StorageEngine) moveToDegraded(sh *shard.Shard, errCount uint32) {
e.mtx.RLock()
defer e.mtx.RUnlock()
sid := sh.ID()
err := sh.SetMode(mode.DegradedReadOnly)
if err != nil {
e.log.Error("failed to move shard in degraded-read-only mode, moving to read-only",
zap.Stringer("shard_id", sid),
zap.Uint32("error count", errCount),
zap.Error(err))
err = sh.SetMode(mode.ReadOnly)
if err != nil {
e.log.Error("failed to move shard in read-only mode",
zap.Stringer("shard_id", sid),
zap.Uint32("error count", errCount),
zap.Error(err))
} else {
e.log.Info("shard is moved in read-only mode due to error threshold",
zap.Stringer("shard_id", sid),
zap.Uint32("error count", errCount))
}
} else {
e.log.Info("shard is moved in degraded mode due to error threshold",
zap.Stringer("shard_id", sid),
zap.Uint32("error count", errCount))
}
}
// reportShardErrorBackground increases shard error counter and logs an error.
// It is intended to be used from background workers and
// doesn't change shard mode because of possible deadlocks.
func (e *StorageEngine) reportShardErrorBackground(id string, msg string, err error) {
e.mtx.RLock()
sh, ok := e.shards[id]
e.mtx.RUnlock()
if !ok {
return
}
if isLogical(err) {
e.log.Warn(msg,
zap.Stringer("shard_id", sh.ID()),
zap.String("error", err.Error()))
return
}
errCount := sh.errorCount.Inc()
e.reportShardErrorWithFlags(sh.Shard, errCount, false, msg, err)
}
// reportShardError checks that the amount of errors doesn't exceed the configured threshold.
// If it does, shard is set to read-only mode.
func (e *StorageEngine) reportShardError(
sh hashedShard,
msg string,
err error,
fields ...zap.Field) {
if isLogical(err) {
e.log.Warn(msg,
zap.Stringer("shard_id", sh.ID()),
zap.String("error", err.Error()))
return
}
errCount := sh.errorCount.Inc()
e.reportShardErrorWithFlags(sh.Shard, errCount, true, msg, err, fields...)
}
func (e *StorageEngine) reportShardErrorWithFlags(
sh *shard.Shard,
errCount uint32,
block bool,
msg string,
err error,
fields ...zap.Field) {
sid := sh.ID()
e.log.Warn(msg, append([]zap.Field{
zap.Stringer("shard_id", sid),
zap.Uint32("error count", errCount),
zap.String("error", err.Error()),
}, fields...)...)
if e.errorsThreshold == 0 || errCount < e.errorsThreshold {
return
}
if block {
e.moveToDegraded(sh, errCount)
} else {
req := setModeRequest{
errorCount: errCount,
sh: sh,
}
select {
case e.setModeCh <- req:
default:
// For background workers we can have a lot of such errors,
// thus logging is done with DEBUG level.
e.log.Debug("mode change is in progress, ignoring set-mode request",
zap.Stringer("shard_id", sid),
zap.Uint32("error_count", errCount))
}
}
}
func isLogical(err error) bool {
return errors.As(err, &logicerr.Logical{})
}
// Option represents StorageEngine's constructor option.
type Option func(*cfg)
type cfg struct {
log *logger.Logger
errorsThreshold uint32
metrics MetricRegister
shardPoolSize uint32
}
func defaultCfg() *cfg {
return &cfg{
log: &logger.Logger{Logger: zap.L()},
shardPoolSize: 20,
}
}
// New creates, initializes and returns new StorageEngine instance.
func New(opts ...Option) *StorageEngine {
c := defaultCfg()
for i := range opts {
opts[i](c)
}
return &StorageEngine{
cfg: c,
mtx: new(sync.RWMutex),
shards: make(map[string]shardWrapper),
shardPools: make(map[string]util.WorkerPool),
closeCh: make(chan struct{}),
setModeCh: make(chan setModeRequest),
}
}
// WithLogger returns option to set StorageEngine's logger.
func WithLogger(l *logger.Logger) Option {
return func(c *cfg) {
c.log = l
}
}
func WithMetrics(v MetricRegister) Option {
return func(c *cfg) {
c.metrics = v
}
}
// WithShardPoolSize returns option to specify size of worker pool for each shard.
func WithShardPoolSize(sz uint32) Option {
return func(c *cfg) {
c.shardPoolSize = sz
}
}
// WithErrorThreshold returns an option to specify size amount of errors after which
// shard is moved to read-only mode.
func WithErrorThreshold(sz uint32) Option {
return func(c *cfg) {
c.errorsThreshold = sz
}
}