github.com/zuoyebang/bitalosdb@v1.1.1-0.20240516111551-79a8c4d8ce20/log_recycler.go (about)

     1  // Copyright 2021 The Bitalosdb author(hustxrb@163.com) and other contributors.
     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 bitalosdb
    16  
    17  import (
    18  	"sync"
    19  
    20  	"github.com/cockroachdb/errors"
    21  )
    22  
    23  type logRecycler struct {
    24  	limit            int
    25  	minRecycleLogNum FileNum
    26  
    27  	mu struct {
    28  		sync.Mutex
    29  		logs      []fileInfo
    30  		maxLogNum FileNum
    31  	}
    32  }
    33  
    34  func (r *logRecycler) add(logInfo fileInfo) bool {
    35  	if logInfo.fileNum < r.minRecycleLogNum {
    36  		return false
    37  	}
    38  
    39  	r.mu.Lock()
    40  	defer r.mu.Unlock()
    41  
    42  	if logInfo.fileNum <= r.mu.maxLogNum {
    43  		return true
    44  	}
    45  	r.mu.maxLogNum = logInfo.fileNum
    46  	if len(r.mu.logs) >= r.limit {
    47  		return false
    48  	}
    49  	r.mu.logs = append(r.mu.logs, logInfo)
    50  	return true
    51  }
    52  
    53  func (r *logRecycler) peek() (fileInfo, bool) {
    54  	r.mu.Lock()
    55  	defer r.mu.Unlock()
    56  
    57  	if len(r.mu.logs) == 0 {
    58  		return fileInfo{}, false
    59  	}
    60  	return r.mu.logs[0], true
    61  }
    62  
    63  func (r *logRecycler) stats() (count int, size uint64) {
    64  	r.mu.Lock()
    65  	defer r.mu.Unlock()
    66  	count = len(r.mu.logs)
    67  	for i := 0; i < count; i++ {
    68  		size += r.mu.logs[i].fileSize
    69  	}
    70  	return count, size
    71  }
    72  
    73  func (r *logRecycler) pop(logNum FileNum) error {
    74  	r.mu.Lock()
    75  	defer r.mu.Unlock()
    76  
    77  	if len(r.mu.logs) == 0 {
    78  		return errors.New("bitalosdb: log recycler empty")
    79  	}
    80  	if r.mu.logs[0].fileNum != logNum {
    81  		return errors.Errorf("bitalosdb: log recycler invalid %d vs %d", errors.Safe(logNum), errors.Safe(fileInfoNums(r.mu.logs)))
    82  	}
    83  	r.mu.logs = r.mu.logs[1:]
    84  	return nil
    85  }
    86  
    87  func fileInfoNums(finfos []fileInfo) []FileNum {
    88  	if len(finfos) == 0 {
    89  		return nil
    90  	}
    91  	nums := make([]FileNum, len(finfos))
    92  	for i := range finfos {
    93  		nums[i] = finfos[i].fileNum
    94  	}
    95  	return nums
    96  }