Ubuntu Repository Cache Charm

  1. Bug #1945304
  2. Activity log

Activity log for bug #1945304

Date Who What changed Old value New value Message
2021-09-28 09:33:59 Thomas Cuthbert bug added bug
2021-09-28 09:35:23 Thomas Cuthbert description The current refresh_patterns for ubuntu-repository-cache don't allow for squid to fetch large upstream debs while still serving from cache. # refresh pattern for debs and udebs refresh_pattern deb$ 129600 100% 129600 refresh_pattern udeb$ 129600 100% 129600 refresh_pattern tar.gz$ 129600 100% 129600 # refresh stats: https://pastebin.ubuntu.com/p/N9NdgWfrGk/ HTTP histogram: Count %Total Category 6571 0.18 Stale: expires time reached 0 0.00 Fresh: refresh_pattern last-mod factor percentage Cache Digests histogram: Count %Total Category 8293 1.65 Stale: expires time reached 3672 0.73 Fresh: refresh_pattern last-mod factor percentage On Store histogram: Count %Total Category 2352 11.26 Fresh: expires time not reached 0 0.00 Fresh: refresh_pattern last-mod factor percentage For example archive.ubuntu.com/ubuntu/pool/restricted/n/nvidia-graphics-drivers-470/libnvidia-gl-470_470.63.01-0ubuntu0.18.04.2_amd64.deb, is 128MB, it's a popular deb and once the refresh timer of 24 hours expires squid's LM-factor is not able to serve semi-stale content while it fetches upstream. I think: refresh_pattern deb$ 129600 100% 129600 refresh_pattern udeb$ 129600 100% 129600 refresh_pattern tar.gz$ 129600 100% 129600 Should be: refresh_pattern deb$ 129600 98% 129600 refresh_pattern udeb$ 129600 98% 129600 refresh_pattern tar.gz$ 129600 98% 129600 So squid has time to fetch larger debs upstream before the Cache-Control: max-age=$secs is reached. The current refresh_patterns for ubuntu-repository-cache don't allow for squid to fetch large upstream debs while still serving from cache. # refresh pattern for debs and udebs refresh_pattern deb$ 129600 100% 129600 refresh_pattern udeb$ 129600 100% 129600 refresh_pattern tar.gz$ 129600 100% 129600 # refresh stats: https://pastebin.ubuntu.com/p/N9NdgWfrGk/ HTTP histogram: Count %Total Category  6571 0.18 Stale: expires time reached      0 0.00 Fresh: refresh_pattern last-mod factor percentage Cache Digests histogram: Count %Total Category   8293 1.65 Stale: expires time reached   3672 0.73 Fresh: refresh_pattern last-mod factor percentage On Store histogram: Count %Total Category   2352 11.26 Fresh: expires time not reached      0 0.00 Fresh: refresh_pattern last-mod factor percentage For example archive.ubuntu.com/ubuntu/pool/restricted/n/nvidia-graphics-drivers-470/libnvidia-gl-470_470.63.01-0ubuntu0.18.04.2_amd64.deb, is 138MB, it's a popular deb and once the refresh timer of 24 hours expires squid's LM-factor is not able to serve semi-stale content while it fetches upstream. https://pastebin.ubuntu.com/p/tNNXDf8c25/ I think: refresh_pattern deb$ 129600 100% 129600 refresh_pattern udeb$ 129600 100% 129600 refresh_pattern tar.gz$ 129600 100% 129600 Should be: refresh_pattern deb$ 129600 98% 129600 refresh_pattern udeb$ 129600 98% 129600 refresh_pattern tar.gz$ 129600 98% 129600 So squid has time to fetch larger debs upstream before the Cache-Control: max-age=$secs is reached.
2021-09-28 09:36:23 Thomas Cuthbert summary deb refresh_pattern has no effect deb refresh_pattern has no effect for large debs
2021-09-28 09:37:55 Thomas Cuthbert summary deb refresh_pattern has no effect for large debs Current refresh_pattern does not work for large debs