go.temporal.io/server@v1.23.0/common/quotas/dynamic.go (about)

     1  // The MIT License
     2  //
     3  // Copyright (c) 2020 Temporal Technologies Inc.  All rights reserved.
     4  //
     5  // Copyright (c) 2020 Uber Technologies, Inc.
     6  //
     7  // Permission is hereby granted, free of charge, to any person obtaining a copy
     8  // of this software and associated documentation files (the "Software"), to deal
     9  // in the Software without restriction, including without limitation the rights
    10  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    11  // copies of the Software, and to permit persons to whom the Software is
    12  // furnished to do so, subject to the following conditions:
    13  //
    14  // The above copyright notice and this permission notice shall be included in
    15  // all copies or substantial portions of the Software.
    16  //
    17  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    18  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    19  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    20  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    21  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    22  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    23  // THE SOFTWARE.
    24  
    25  package quotas
    26  
    27  import (
    28  	"go.uber.org/atomic"
    29  )
    30  
    31  type (
    32  	// RateFn returns a float64 as the RPS
    33  	RateFn func() float64
    34  
    35  	// NamespaceRateFn returns a float64 as the RPS for the given namespace
    36  	NamespaceRateFn func(namespace string) float64
    37  
    38  	// BurstFn returns an int as the burst / bucket size
    39  	BurstFn func() int
    40  
    41  	// NamespaceBurstFn returns an int as the burst / bucket size for the given namespace
    42  	NamespaceBurstFn func(namespace string) float64
    43  
    44  	// RateBurst returns rate & burst for rate limiter
    45  	RateBurst interface {
    46  		Rate() float64
    47  		Burst() int
    48  	}
    49  
    50  	RateBurstImpl struct {
    51  		rateFn  RateFn
    52  		burstFn BurstFn
    53  	}
    54  
    55  	// MutableRateBurstImpl stores the dynamic rate & burst for rate limiter
    56  	MutableRateBurstImpl struct {
    57  		rate  *atomic.Float64
    58  		burst *atomic.Int64
    59  	}
    60  
    61  	MutableRateBurst interface {
    62  		SetRPS(rps float64)
    63  		SetBurst(burst int)
    64  		RateBurst
    65  	}
    66  )
    67  
    68  func NewRateBurst(
    69  	rateFn RateFn,
    70  	burstFn BurstFn,
    71  ) *RateBurstImpl {
    72  	return &RateBurstImpl{
    73  		rateFn:  rateFn,
    74  		burstFn: burstFn,
    75  	}
    76  }
    77  
    78  func NewDefaultIncomingRateBurst(
    79  	rateFn RateFn,
    80  ) *RateBurstImpl {
    81  	return newDefaultRateBurst(rateFn, defaultIncomingRateBurstRatio)
    82  }
    83  
    84  func NewDefaultOutgoingRateBurst(
    85  	rateFn RateFn,
    86  ) *RateBurstImpl {
    87  	return newDefaultRateBurst(rateFn, defaultOutgoingRateBurstRatio)
    88  }
    89  
    90  func newDefaultRateBurst(
    91  	rateFn RateFn,
    92  	rateToBurstRatio float64,
    93  ) *RateBurstImpl {
    94  	burstFn := func() int {
    95  		rate := rateFn()
    96  		if rate < 0 {
    97  			rate = 0
    98  		}
    99  		if rateToBurstRatio < 0 {
   100  			rateToBurstRatio = 0
   101  		}
   102  		burst := int(rate * rateToBurstRatio)
   103  		if burst == 0 && rate > 0 && rateToBurstRatio > 0 {
   104  			burst = 1
   105  		}
   106  		return burst
   107  	}
   108  	return NewRateBurst(rateFn, burstFn)
   109  }
   110  
   111  func (d *RateBurstImpl) Rate() float64 {
   112  	return d.rateFn()
   113  }
   114  
   115  func (d *RateBurstImpl) Burst() int {
   116  	return d.burstFn()
   117  }
   118  
   119  func NewMutableRateBurst(
   120  	rate float64,
   121  	burst int,
   122  ) *MutableRateBurstImpl {
   123  	return &MutableRateBurstImpl{
   124  		rate:  atomic.NewFloat64(rate),
   125  		burst: atomic.NewInt64(int64(burst)),
   126  	}
   127  }
   128  
   129  func (d *MutableRateBurstImpl) SetRPS(rate float64) {
   130  	d.rate.Store(rate)
   131  }
   132  
   133  func (d *MutableRateBurstImpl) SetBurst(burst int) {
   134  	d.burst.Store(int64(burst))
   135  }
   136  
   137  func (d *MutableRateBurstImpl) Rate() float64 {
   138  	return d.rate.Load()
   139  }
   140  
   141  func (d *MutableRateBurstImpl) Burst() int {
   142  	return int(d.burst.Load())
   143  }