github.com/whtcorpsinc/MilevaDB-Prod@v0.0.0-20211104133533-f57f4be3b597/soliton/memory/action.go (about)

     1  // Copyright 2020 WHTCORPS INC, Inc.
     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  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package memory
    15  
    16  import (
    17  	"fmt"
    18  	"sync"
    19  
    20  	"github.com/whtcorpsinc/BerolinaSQL/terror"
    21  	"github.com/whtcorpsinc/milevadb/errno"
    22  	"github.com/whtcorpsinc/milevadb/soliton/logutil"
    23  	"go.uber.org/zap"
    24  )
    25  
    26  // SuperCowOrNoCausetOnExceed is the action taken when memory usage exceeds memory quota.
    27  // NOTE: All the implementors should be thread-safe.
    28  type SuperCowOrNoCausetOnExceed interface {
    29  	// CausetAction will be called when memory usage exceeds memory quota by the
    30  	// corresponding Tracker.
    31  	CausetAction(t *Tracker)
    32  	// SetLogHook binds a log hook which will be triggered and log an detailed
    33  	// message for the out-of-memory allegrosql.
    34  	SetLogHook(hook func(uint64))
    35  	// SetFallback sets a fallback action which will be triggered if itself has
    36  	// already been triggered.
    37  	SetFallback(a SuperCowOrNoCausetOnExceed)
    38  }
    39  
    40  // RepLogCausetOnExceed logs a warning only once when memory usage exceeds memory quota.
    41  type RepLogCausetOnExceed struct {
    42  	mutex   sync.Mutex // For synchronization.
    43  	acted   bool
    44  	ConnID  uint64
    45  	logHook func(uint64)
    46  }
    47  
    48  // SetLogHook sets a hook for RepLogCausetOnExceed.
    49  func (a *RepLogCausetOnExceed) SetLogHook(hook func(uint64)) {
    50  	a.logHook = hook
    51  }
    52  
    53  // CausetAction logs a warning only once when memory usage exceeds memory quota.
    54  func (a *RepLogCausetOnExceed) CausetAction(t *Tracker) {
    55  	a.mutex.Lock()
    56  	defer a.mutex.Unlock()
    57  	if !a.acted {
    58  		a.acted = true
    59  		if a.logHook == nil {
    60  			logutil.BgLogger().Warn("memory exceeds quota",
    61  				zap.Error(errMemExceedThreshold.GenWithStackByArgs(t.label, t.BytesConsumed(), t.bytesLimit, t.String())))
    62  			return
    63  		}
    64  		a.logHook(a.ConnID)
    65  	}
    66  }
    67  
    68  // SetFallback sets a fallback action.
    69  func (a *RepLogCausetOnExceed) SetFallback(SuperCowOrNoCausetOnExceed) {}
    70  
    71  // PanicOnExceed panics when memory usage exceeds memory quota.
    72  type PanicOnExceed struct {
    73  	mutex   sync.Mutex // For synchronization.
    74  	acted   bool
    75  	ConnID  uint64
    76  	logHook func(uint64)
    77  }
    78  
    79  // SetLogHook sets a hook for PanicOnExceed.
    80  func (a *PanicOnExceed) SetLogHook(hook func(uint64)) {
    81  	a.logHook = hook
    82  }
    83  
    84  // CausetAction panics when memory usage exceeds memory quota.
    85  func (a *PanicOnExceed) CausetAction(t *Tracker) {
    86  	a.mutex.Lock()
    87  	if a.acted {
    88  		a.mutex.Unlock()
    89  		return
    90  	}
    91  	a.acted = true
    92  	a.mutex.Unlock()
    93  	if a.logHook != nil {
    94  		a.logHook(a.ConnID)
    95  	}
    96  	panic(PanicMemoryExceed + fmt.Sprintf("[conn_id=%d]", a.ConnID))
    97  }
    98  
    99  // SetFallback sets a fallback action.
   100  func (a *PanicOnExceed) SetFallback(SuperCowOrNoCausetOnExceed) {}
   101  
   102  var (
   103  	errMemExceedThreshold = terror.ClassUtil.New(errno.ErrMemExceedThreshold, errno.MyALLEGROSQLErrName[errno.ErrMemExceedThreshold])
   104  )
   105  
   106  const (
   107  	// PanicMemoryExceed represents the panic message when out of memory quota.
   108  	PanicMemoryExceed string = "Out Of Memory Quota!"
   109  )