tree e16ff020564eae788f69dfc1cf4c630e8445bc34
parent b66414979781efc00889800ae83b2c478de7abf2
author Jacek Centkowski <geminica.programs@gmail.com> 1661958816 +0200
committer Jacek Centkowski <geminica.programs@gmail.com> 1663134221 +0200

Remove metrics when cache gets closed

When plugin with persistent caches gets reloaded it fails to load with
the following exception:

  java.lang.IllegalArgumentException: A metric named cache/chroniclemap/percentage_free_space_test-cache-plugin_test_cache already exists
  ...

The problem is caused by cache related metrics that are created when
cache-chroniclemap instantiates the persistent cache implementation for
plugin that is being reloaded.

This change ensures that all cache related metrics are removed when cache is
closed.

Notes:
* This is the necessary but not sufficient step to solve #15587.
  It is enough to solve the happy path when 'Gerrit-ReloadMode: restart'.
  IOW when the old version of plugin with persistent caches gets unloaded
  before the new version is loaded.
* Description on how to reload plugin with persistent caches when
  cache-chroniclemap lib-module is installed was added to migration.md

Bug: Issue 15587
Depends-On: I06d48535702a8acd0bcb4e1315a35b3c1d1768cb
Change-Id: I03e34dd3463fad00ba8fbc174597c896a93db547