status-go/vendor/github.com/tsenart/tb

Token Bucket (tb)

This package provides a generic lock-free implementation of the "Token bucket" algorithm where handling of non-conformity is left to the user.

The token bucket is an algorithm used in packet switched computer networks and telecommunications networks. It can be used to check that data transmissions, in the form of packets, conform to defined limits on bandwidth and burstiness (a measure of the unevenness or variations in the traffic flow) -- Wikipedia

This implementation of the token bucket generalises its applications beyond packet rate conformance. Hence, the word generic. You can use it to throttle any flow over time as long as it can be expressed as a number (bytes/s, requests/s, messages/s, packets/s, potatoes/s, heartbeats/s, etc...).

The lock-free part of the description refers to the lock-free programming techniques (CAS loop) used in the core Bucket methods (Take and Put). Here is a good overview of lock-free programming you can refer to.

All utility pacakges such as http and io are just wrappers around the core package. This ought to be your one stop shop for all things throttling in Go so feel free to propose missing common functionality.

Install

$ go get github.com/tsenart/tb

Usage

Read up the docs and have a look at some examples.

Licence

The MIT License (MIT)

Copyright (c) 2014-2015 Tomás Senart

Permission is hereby granted, free of charge, to any person obtaining a copy of
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The above copyright notice and this permission notice shall be included in all
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