forgejo/modules/queue/workerqueue.go
wxiaoguang 58dfaf3a75
Improve queue & process & stacktrace ()
Although some features are mixed together in this PR, this PR is not
that large, and these features are all related.

Actually there are more than 70 lines are for a toy "test queue", so
this PR is quite simple.

Major features:

1. Allow site admin to clear a queue (remove all items in a queue)
* Because there is no transaction, the "unique queue" could be corrupted
in rare cases, that's unfixable.
* eg: the item is in the "set" but not in the "list", so the item would
never be able to be pushed into the queue.
* Now site admin could simply clear the queue, then everything becomes
correct, the lost items could be re-pushed into queue by future
operations.
3. Split the "admin/monitor" to separate pages
4. Allow to download diagnosis report
* In history, there were many users reporting that Gitea queue gets
stuck, or Gitea's CPU is 100%
    * With diagnosis report, maintainers could know what happens clearly

The diagnosis report sample:
[gitea-diagnosis-20230510-192913.zip](https://github.com/go-gitea/gitea/files/11441346/gitea-diagnosis-20230510-192913.zip)
, use "go tool pprof profile.dat" to view the report.


Screenshots:


![image](https://github.com/go-gitea/gitea/assets/2114189/320659b4-2eda-4def-8dc0-5ea08d578063)


![image](https://github.com/go-gitea/gitea/assets/2114189/c5c46fae-9dc0-44ca-8cd3-57beedc5035e)


![image](https://github.com/go-gitea/gitea/assets/2114189/6168a811-42a1-4e64-a263-0617a6c8c4fe)

---------

Co-authored-by: Jason Song <i@wolfogre.com>
Co-authored-by: Giteabot <teabot@gitea.io>
2023-05-11 07:45:47 +00:00

246 lines
6.7 KiB
Go

// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package queue
import (
"context"
"fmt"
"sync"
"sync/atomic"
"time"
"code.gitea.io/gitea/modules/graceful"
"code.gitea.io/gitea/modules/json"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
)
// WorkerPoolQueue is a queue that uses a pool of workers to process items
// It can use different underlying (base) queue types
type WorkerPoolQueue[T any] struct {
ctxRun context.Context
ctxRunCancel context.CancelFunc
ctxShutdown atomic.Pointer[context.Context]
shutdownDone chan struct{}
origHandler HandlerFuncT[T]
safeHandler HandlerFuncT[T]
baseQueueType string
baseConfig *BaseConfig
baseQueue baseQueue
batchChan chan []T
flushChan chan flushType
batchLength int
workerNum int
workerMaxNum int
workerActiveNum int
workerNumMu sync.Mutex
}
type flushType chan struct{}
var _ ManagedWorkerPoolQueue = (*WorkerPoolQueue[any])(nil)
func (q *WorkerPoolQueue[T]) GetName() string {
return q.baseConfig.ManagedName
}
func (q *WorkerPoolQueue[T]) GetType() string {
return q.baseQueueType
}
func (q *WorkerPoolQueue[T]) GetItemTypeName() string {
var t T
return fmt.Sprintf("%T", t)
}
func (q *WorkerPoolQueue[T]) GetWorkerNumber() int {
q.workerNumMu.Lock()
defer q.workerNumMu.Unlock()
return q.workerNum
}
func (q *WorkerPoolQueue[T]) GetWorkerActiveNumber() int {
q.workerNumMu.Lock()
defer q.workerNumMu.Unlock()
return q.workerActiveNum
}
func (q *WorkerPoolQueue[T]) GetWorkerMaxNumber() int {
q.workerNumMu.Lock()
defer q.workerNumMu.Unlock()
return q.workerMaxNum
}
func (q *WorkerPoolQueue[T]) SetWorkerMaxNumber(num int) {
q.workerNumMu.Lock()
defer q.workerNumMu.Unlock()
q.workerMaxNum = num
}
func (q *WorkerPoolQueue[T]) GetQueueItemNumber() int {
cnt, err := q.baseQueue.Len(q.ctxRun)
if err != nil {
log.Error("Failed to get number of items in queue %q: %v", q.GetName(), err)
}
return cnt
}
func (q *WorkerPoolQueue[T]) FlushWithContext(ctx context.Context, timeout time.Duration) (err error) {
if q.isBaseQueueDummy() {
return
}
log.Debug("Try to flush queue %q with timeout %v", q.GetName(), timeout)
defer log.Debug("Finish flushing queue %q, err: %v", q.GetName(), err)
var after <-chan time.Time
after = infiniteTimerC
if timeout > 0 {
after = time.After(timeout)
}
c := make(flushType)
// send flush request
// if it blocks, it means that there is a flush in progress or the queue hasn't been started yet
select {
case q.flushChan <- c:
case <-ctx.Done():
return ctx.Err()
case <-q.ctxRun.Done():
return q.ctxRun.Err()
case <-after:
return context.DeadlineExceeded
}
// wait for flush to finish
select {
case <-c:
return nil
case <-ctx.Done():
return ctx.Err()
case <-q.ctxRun.Done():
return q.ctxRun.Err()
case <-after:
return context.DeadlineExceeded
}
}
// RemoveAllItems removes all items in the baes queue
func (q *WorkerPoolQueue[T]) RemoveAllItems(ctx context.Context) error {
return q.baseQueue.RemoveAll(ctx)
}
func (q *WorkerPoolQueue[T]) marshal(data T) []byte {
bs, err := json.Marshal(data)
if err != nil {
log.Error("Failed to marshal item for queue %q: %v", q.GetName(), err)
return nil
}
return bs
}
func (q *WorkerPoolQueue[T]) unmarshal(data []byte) (t T, ok bool) {
if err := json.Unmarshal(data, &t); err != nil {
log.Error("Failed to unmarshal item from queue %q: %v", q.GetName(), err)
return t, false
}
return t, true
}
func (q *WorkerPoolQueue[T]) isBaseQueueDummy() bool {
_, isDummy := q.baseQueue.(*baseDummy)
return isDummy
}
// Push adds an item to the queue, it may block for a while and then returns an error if the queue is full
func (q *WorkerPoolQueue[T]) Push(data T) error {
if q.isBaseQueueDummy() && q.safeHandler != nil {
// FIXME: the "immediate" queue is only for testing, but it really causes problems because its behavior is different from a real queue.
// Even if tests pass, it doesn't mean that there is no bug in code.
if data, ok := q.unmarshal(q.marshal(data)); ok {
q.safeHandler(data)
}
}
return q.baseQueue.PushItem(q.ctxRun, q.marshal(data))
}
// Has only works for unique queues. Keep in mind that this check may not be reliable (due to lacking of proper transaction support)
// There could be a small chance that duplicate items appear in the queue
func (q *WorkerPoolQueue[T]) Has(data T) (bool, error) {
return q.baseQueue.HasItem(q.ctxRun, q.marshal(data))
}
func (q *WorkerPoolQueue[T]) Run(atShutdown, atTerminate func(func())) {
atShutdown(func() {
// in case some queue handlers are slow or have hanging bugs, at most wait for a short time
q.ShutdownWait(1 * time.Second)
})
q.doRun()
}
// ShutdownWait shuts down the queue, waits for all workers to finish their jobs, and pushes the unhandled items back to the base queue
// It waits for all workers (handlers) to finish their jobs, in case some buggy handlers would hang forever, a reasonable timeout is needed
func (q *WorkerPoolQueue[T]) ShutdownWait(timeout time.Duration) {
shutdownCtx, shutdownCtxCancel := context.WithTimeout(context.Background(), timeout)
defer shutdownCtxCancel()
if q.ctxShutdown.CompareAndSwap(nil, &shutdownCtx) {
q.ctxRunCancel()
}
<-q.shutdownDone
}
func getNewQueueFn(t string) (string, func(cfg *BaseConfig, unique bool) (baseQueue, error)) {
switch t {
case "dummy", "immediate":
return t, newBaseDummy
case "channel":
return t, newBaseChannelGeneric
case "redis":
return t, newBaseRedisGeneric
default: // level(leveldb,levelqueue,persistable-channel)
return "level", newBaseLevelQueueGeneric
}
}
func NewWorkerPoolQueueBySetting[T any](name string, queueSetting setting.QueueSettings, handler HandlerFuncT[T], unique bool) (*WorkerPoolQueue[T], error) {
if handler == nil {
log.Debug("Use dummy queue for %q because handler is nil and caller doesn't want to process the queue items", name)
queueSetting.Type = "dummy"
}
var w WorkerPoolQueue[T]
var err error
queueType, newQueueFn := getNewQueueFn(queueSetting.Type)
w.baseQueueType = queueType
w.baseConfig = toBaseConfig(name, queueSetting)
w.baseQueue, err = newQueueFn(w.baseConfig, unique)
if err != nil {
return nil, err
}
log.Trace("Created queue %q of type %q", name, queueType)
w.ctxRun, w.ctxRunCancel = context.WithCancel(graceful.GetManager().ShutdownContext())
w.batchChan = make(chan []T)
w.flushChan = make(chan flushType)
w.shutdownDone = make(chan struct{})
w.workerMaxNum = queueSetting.MaxWorkers
w.batchLength = queueSetting.BatchLength
w.origHandler = handler
w.safeHandler = func(t ...T) (unhandled []T) {
defer func() {
err := recover()
if err != nil {
log.Error("Recovered from panic in queue %q handler: %v\n%s", name, err, log.Stack(2))
}
}()
return w.origHandler(t...)
}
return &w, nil
}