[JIRA] (OVIRT-921) Smarter cache handling for mock_runner.sh

Smarter cache handling for mock_runner.sh ----------------------------------------- Key: OVIRT-921 URL: https://ovirt-jira.atlassian.net/browse/OVIRT-921 Project: oVirt - virtualization made easy Issue Type: Improvement Components: mock_runner Reporter: Barak Korren Assignee: infra Labels: mock, mock_runner.sh, performance, standard-ci We've improved our handing of mock caches in OVIRT-902, but it could be better. Right now we're just deleting everything from {{mock_cleanup.sh}} every two days, but we could do things in a smarter and more refined way: * Mock actually has two separate caches that could be handled separately: *# The yum cache - Caches package that are installed in the chroot *# The root cache - Keeps an archive of the whole chroot * We can make the yum cache shared by all the chroots that use the same repos * We can keep the yum cache for much longer since 'yum' will refresh it automatically. We can tune this from mock root config file: ** {{config_opts\['plugin_conf']\['yum_cache_opts']\['max_age_days']}} ** {{config_opts\['plugin_conf']\['yum_cache_opts']\['max_metadata_age_days']}} * We can also control the chroot cache from the mock config file, this will allow us greated flexibility, like deciding that some chroots live longer: ** {{config_opts\['plugin_conf']\['root_cache_opts']\['max_age_days']}} * We can use a different compression algorithm for the chroot acche, this may yield better performance. * We still need some cleanup in {{moch_cleanup.sh}} but only for chroot caches that ahvn't been in use for a long time.