HashXXmod

Purpose

Generates a number which is mod of given string’s hash.

hash32mod(literal_string, modulo) / hash32mod(literal_string, modulo, seed)

Generates a number which is calculated on (32 bit hash of the given string % modulo)
  • If modulo is not a valid number, then 0 is returned.
  • If modulo is 0, then 0 is returned.
  • Seed is an optional parameter with default = 0.
  • If seed is not a valid unsigned number, then 0 is returned.

hash64mod(literal_string, modulo) / hash64mod(literal_string, modulo, seed)

Generates a number which is calculated on (64 bit hash of the given string % modulo)
  • If modulo is not a valid number, then 0 is returned.
  • If modulo is 0, then 0 is returned.
  • Seed is an optional parameter with default = 0.
  • If seed is not a valid unsigned number, then 0 is returned.

Warning

  • Default hash implementation is non-crypto.
  • To use xxhash enable compile time flag.

Example

module(load="fmhash")

if (hash64mod($!msg!request_id, 100) <= 30) then {
 //send out
}

See also

Hash based sampling

See also

Help with configuring/using Rsyslog:

  • Mailing list - best route for general questions
  • GitHub: rsyslog source project - detailed questions, reporting issues that are believed to be bugs with Rsyslog
  • Stack Exchange (View, Ask) - experimental support from rsyslog community

See also

Contributing to Rsyslog:

Copyright 2008-2020 Rainer Gerhards (Großrinderfeld), and Others.