ExqLimit v0.1.3 ExqLimit.GCRA View Source
This module implements the GCRA algorithm. Check the blog post by brandur for an excellent introduction.
Example
{ExqLimit.GCRA, period: :hour, rate: 60}The above config can be used to run 60 jobs per hour. The algorithm only allows jobs at regular interval, so if 10 jobs get enqueued at once, each one will get processed at 1 minute interval.
{ExqLimit.GCRA, period: :hour, rate: 60, burst: 5}burst option provides the ability to overshoot the limit for a
short period of time. It can be compared to a battery. With the
above config, when it's fully charged, it can process 5 jobs
immediatly, but from 6th job onwards, it will process jobs at 1
minute interval. The battery will get recharged 1 point every minute
and get maxed at 5.
Options
period(atom | integer) - Can be either:second,:minute,:hour,:day. In case of integer, it will be consider as seconds. Required field.burst(integer) - Number of jobs allowed over the limit. Defaults to 0local(boolean) - if set to true, the rate limiting will apply to the local worker node. Otherwise, the rate limiting will apply to all worker nodes. Defaults tofalse.node_id(string) - Unique id of the worker node. Defaults to Exq node identifier. This will be used only if local option is set to true.
Credits
The lua script used in this module is a slightly modified version of redis-gcra