On Fri, 12 Aug 2022 at 20:34, Sean Rose <[email protected]> wrote: > If "something is blocking the deletion of those files", wouldn't that also > block renaming the cache folder? >
Usually what's "blocking" the deletion is a slow disk. A rename operation is just one operation, so it should complete much faster than removing thousands of files. On Thu, Aug 11, 2022 at 6:23 AM Valentin Gosu <[email protected]> > wrote: > >> On Thu, 11 Aug 2022 at 15:13, Paul Zühlcke <[email protected]> wrote: >> >>> This is awesome! Thanks for working on it. >>> What happens if the disk cache clearing hasn't finished when user starts >>> Firefox again? Will they still be able to use the cache? >>> >> >> Good question. The cache folder is renamed, prior to deletion, so we can >> be sure the background task has exclusive access to it. A new instance >> would start with a completely new cache folder, even if the background task >> hasn't finished deleting the old one yet. >> >> PS. Sorry for forgetting the subject in my previous email 🙂 >> >> >>> On Thu, 11 Aug 2022 at 14:50, Valentin Gosu <[email protected]> >>> wrote: >>> >>>> Hi everyone, >>>> >>>> As Bug 1705676 - Investigate purging HTTP disk cache using >>>> backgroundtasks (out-of-process) >>>> <https://bugzilla.mozilla.org/show_bug.cgi?id=1705676> is getting >>>> closer to landing, I wanted to give everyone a heads-up about this change >>>> and the reasoning behind it. >>>> >>>> We have a non-default setting in the History settings preferences panel >>>> where you may choose to "Clear History when Firefox closes" - which sets >>>> the privacy.sanitize.sanitizeOnShutdown pref. If the Cache checkbox is also >>>> checked that sets the privacy.clearOnShutdown.cache pref to true. >>>> When both of these prefs are true CacheObserver::ClearCacheOnShutdown() >>>> will return true, which will cause Firefox to clear the HTTP disk cache >>>> during shutdown. This will block shutdown for however long this takes. If >>>> the user has a slow disk, or the user is on Windows and something is >>>> blocking the deletion of those files, this will trigger a shutdown hang >>>> making Firefox crash. This also leads to a bad user experience as trying to >>>> start Firefox again during this time will show the "Firefox is already >>>> running message". Eventually a crash dump is produced. Bug 1356853 and bug >>>> 1682899 are caused by this specific issue. >>>> >>>> In order to avoid these shutdown hangs, we have introduced a new >>>> mechanism that uses background tasks >>>> <https://firefox-source-docs.mozilla.org/toolkit/components/backgroundtasks/index.html> >>>> to delegate the deletion of the cache to a separate process that may >>>> outlive Firefox. Even if this process is unexpectedly killed (as may happen >>>> during shutdown), we spawn it again after Firefox starts up to clean up any >>>> directories that may be left. >>>> >>>> *The plan is to enable this on Windows Nightly in the next few days to >>>> evaluate if this does indeed work as expected. Assuming it doesn't cause >>>> any issues, we plan to ship it to beta and release at a later date.* >>>> >>>> Please let me know if you have any concerns. Many thanks to Nick >>>> Alexander who supported this effort with a lot of reviews and improvements >>>> to backgroundtasks. >>>> >>>> Thanks, >>>> Valentin >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "[email protected]" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/a/mozilla.org/d/msgid/dev-platform/CACQYfiKjNJVMMkPZy%2BF9AXiO1fJ4ieLhRYgwrkwwPRAe3STDWQ%40mail.gmail.com >>>> <https://groups.google.com/a/mozilla.org/d/msgid/dev-platform/CACQYfiKjNJVMMkPZy%2BF9AXiO1fJ4ieLhRYgwrkwwPRAe3STDWQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- >> You received this message because you are subscribed to the Google Groups >> "[email protected]" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/a/mozilla.org/d/msgid/dev-platform/CACQYfiLxz5504%2BiLAHNnz-jv%3DqFb8fZp2KOuKySSMphxEswvnA%40mail.gmail.com >> <https://groups.google.com/a/mozilla.org/d/msgid/dev-platform/CACQYfiLxz5504%2BiLAHNnz-jv%3DqFb8fZp2KOuKySSMphxEswvnA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "[email protected]" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/a/mozilla.org/d/msgid/dev-platform/CACQYfi%2Bs7H5qbcsRz%2BkqBdDN%3DE690twfcPz35KeuNGGamKWk%3Dw%40mail.gmail.com.
