tree fcfd87c220e07253fac0f1b3e6aad10b64f6536b
parent c8b39c2fe54129a1a624c083a64ce4b3c193d48e
author Jacek Centkowski <geminica.programs@gmail.com> 1663137320 +0200
committer Jacek Centkowski <geminica.programs@gmail.com> 1667470404 +0100

Introduce metric for caches that fall back to default config

Cache chroniclemap relies heavily on configuration (especially on
average key and values sizes) so that its performance can be optimal.
What is more starting with `stable-3.4` there are 7 core caches that
are missing their configuration in Defaults and use fall-back
configuration. It is strongly adviced to auto-tune them (see
'tuning.md') and store dedicated configuration in 'gerrit.config'.

Issuing a warning in such case is not a perfect solution as Gerrit core
caches are initiated very early during the server start hence messages
are not always visible in the log. For this reason the following metric
was introduced:

* 'cache/chroniclemap/caches_without_configuration' that could be used
  as an alarm source as it contains the total number of caches that
  miss the dedicated configuration in 'gerrit.config' and use defaults

Notes:
* adding cache configuration to `gerrit.config` is not considered as
  default configuration
* additionally, the 'auto-adjust-caches' command was extended with
  'adjust-caches-on-defaults' option (see the tuning.md for details)
  that it can be used to tune all caches that fall back to defaults

Bug: Issue 15865
Change-Id: I8b0835c6d8a8ae96832371b79afd2a11f69f09b9