github.com/matrixorigin/matrixone@v1.2.0/pkg/vm/engine/tae/logstore/sm/loop.go (about)

     1  // Copyright 2021 Matrix Origin
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package sm
    16  
    17  import (
    18  	"context"
    19  	"sync"
    20  )
    21  
    22  type Loop struct {
    23  	queue        chan any
    24  	fn           func([]any, chan any)
    25  	nextQueue    chan any
    26  	queueCtx     context.Context
    27  	cancelFn     context.CancelFunc
    28  	wg           *sync.WaitGroup
    29  	maxBatchSize int
    30  
    31  	Itemcount int
    32  	Itemtimes int
    33  }
    34  
    35  func NewLoop(queue, nextQueue chan any, fn func([]any, chan any), maxBatchSize int) *Loop {
    36  	return &Loop{
    37  		queue:        queue,
    38  		fn:           fn,
    39  		nextQueue:    nextQueue,
    40  		maxBatchSize: maxBatchSize,
    41  	}
    42  }
    43  
    44  func (l *Loop) Start() {
    45  	l.queueCtx, l.cancelFn = context.WithCancel(context.Background())
    46  	l.wg = &sync.WaitGroup{}
    47  	l.wg.Add(1)
    48  	go l.loop()
    49  }
    50  
    51  func (l *Loop) loop() {
    52  	defer l.wg.Done()
    53  	for {
    54  		batch := make([]any, 0)
    55  		select {
    56  		case <-l.queueCtx.Done():
    57  			return
    58  		case item := <-l.queue:
    59  			batch = append(batch, item)
    60  		Left:
    61  			for i := 0; i < l.maxBatchSize; i++ {
    62  				select {
    63  				case item = <-l.queue:
    64  					batch = append(batch, item)
    65  				default:
    66  					break Left
    67  				}
    68  			}
    69  		}
    70  		l.Itemcount += len(batch)
    71  		l.Itemtimes++
    72  		l.fn(batch, l.nextQueue)
    73  	}
    74  }
    75  
    76  func (l *Loop) Stop() {
    77  	l.cancelFn()
    78  	l.wg.Wait()
    79  }