githaven-fork/modules/graceful/context.go
zeripath ba526ceffe
Multiple Queue improvements: LevelDB Wait on empty, shutdown empty shadow level queue, reduce goroutines etc (#15693)
* move shutdownfns, terminatefns and hammerfns out of separate goroutines

Coalesce the shutdownfns etc into a list of functions that get run at shutdown
rather then have them run at goroutines blocked on selects.

This may help reduce the background select/poll load in certain
configurations.

* The LevelDB queues can actually wait on empty instead of polling

Slight refactor to cause leveldb queues to wait on empty instead of polling.

* Shutdown the shadow level queue once it is empty

* Remove bytefifo additional goroutine for readToChan as it can just be run in run

* Remove additional removeWorkers goroutine for workers

* Simplify the AtShutdown and AtTerminate functions and add Channel Flusher

* Add shutdown flusher to CUQ

* move persistable channel shutdown stuff to Shutdown Fn

* Ensure that UPCQ has the correct config

* handle shutdown during the flushing

* reduce risk of race between zeroBoost and addWorkers

* prevent double shutdown

Signed-off-by: Andrew Thornton <art27@cantab.net>
2021-05-15 16:22:26 +02:00

74 lines
2.2 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package graceful
import (
"context"
"time"
)
// ChannelContext is a context that wraps a channel and error as a context
type ChannelContext struct {
done <-chan struct{}
err error
}
// NewChannelContext creates a ChannelContext from a channel and error
func NewChannelContext(done <-chan struct{}, err error) *ChannelContext {
return &ChannelContext{
done: done,
err: err,
}
}
// Deadline returns the time when work done on behalf of this context
// should be canceled. There is no Deadline for a ChannelContext
func (ctx *ChannelContext) Deadline() (deadline time.Time, ok bool) {
return
}
// Done returns the channel provided at the creation of this context.
// When closed, work done on behalf of this context should be canceled.
func (ctx *ChannelContext) Done() <-chan struct{} {
return ctx.done
}
// Err returns nil, if Done is not closed. If Done is closed,
// Err returns the error provided at the creation of this context
func (ctx *ChannelContext) Err() error {
select {
case <-ctx.done:
return ctx.err
default:
return nil
}
}
// Value returns nil for all calls as no values are or can be associated with this context
func (ctx *ChannelContext) Value(key interface{}) interface{} {
return nil
}
// ShutdownContext returns a context.Context that is Done at shutdown
// Callers using this context should ensure that they are registered as a running server
// in order that they are waited for.
func (g *Manager) ShutdownContext() context.Context {
return g.shutdownCtx
}
// HammerContext returns a context.Context that is Done at hammer
// Callers using this context should ensure that they are registered as a running server
// in order that they are waited for.
func (g *Manager) HammerContext() context.Context {
return g.hammerCtx
}
// TerminateContext returns a context.Context that is Done at terminate
// Callers using this context should ensure that they are registered as a terminating server
// in order that they are waited for.
func (g *Manager) TerminateContext() context.Context {
return g.terminateCtx
}