github.com/m3db/m3@v1.5.0/src/m3ninx/postings/pool.go (about)

     1  // Copyright (c) 2017 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package postings
    22  
    23  import (
    24  	xpool "github.com/m3db/m3/src/x/pool"
    25  )
    26  
    27  const (
    28  	defaultPoolSize = 8
    29  )
    30  
    31  type pool struct {
    32  	pool xpool.ObjectPool
    33  }
    34  
    35  // PoolAllocateFn returns a new MutableList.
    36  type PoolAllocateFn func() MutableList
    37  
    38  // NewPool returns a new Pool.
    39  func NewPool(
    40  	opts xpool.ObjectPoolOptions,
    41  	allocator PoolAllocateFn,
    42  ) Pool {
    43  	if opts == nil {
    44  		// Use a small pool by default, postings lists can become
    45  		// very large and can be dangerous to pool in any significant
    46  		// quantity (have observed individual postings lists of size 4mb
    47  		// frequently even when reset).
    48  		opts = xpool.NewObjectPoolOptions().SetSize(defaultPoolSize)
    49  	}
    50  
    51  	p := &pool{
    52  		pool: xpool.NewObjectPool(opts),
    53  	}
    54  	p.pool.Init(func() interface{} {
    55  		return allocator()
    56  	})
    57  	return p
    58  }
    59  
    60  func (p *pool) Get() MutableList {
    61  	return p.pool.Get().(MutableList)
    62  }
    63  
    64  func (p *pool) Put(pl MutableList) {
    65  	pl.Reset()
    66  	p.pool.Put(pl)
    67  }