I can also confirm that the fixes in -proposed fixes some severe performance issues on my system, with an encrypted ZFS root filesystem.
It should be noted that if you're using ZFS on an Intel machine with < 4 physical cores, these performance regressions are severe enough to cause the entire machine to noticeably stutter and freeze when the disk is accessed - so this is a fairly serious performance regression for a lot of laptop users! I think the reason why it's so severe on this configuration is due to ZFS read/write spawning 4 tasks, which have a niceness of -20 causing the userspace to be starved (and perhaps security mitigations stopping/hindering the userspace from using hyperthreading). -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to zfs-linux in Ubuntu. https://bugs.launchpad.net/bugs/1969482 Title: zfs-2.1.4+ sru Status in zfs-linux package in Ubuntu: Fix Released Status in zfs-linux source package in Jammy: Fix Committed Bug description: [Impact] * Upstream stable point release update with bugfixes, performance fixes, and newer kernel support as needed already in the OEM kernel and will be needed in the future HWE kernels. [Test Plan] * autopkgtest pass * kernel regression zfs testsuite pass * zsys integration test pass [Where problems could occur] * The stable branches maintain api/abi. Certain bugfixes do change userspace visible behavior of either succeeeding (when previously operations failed), or return errors when previously succeeding in error. For example there are changes when unlinking files in full volumes; changes to fallocate behaviour, etc. Overall they are minor corner cases, and bugfixes to correct the bahaviour to what is universally expected and how things behave on other filesystems (i.e. ext4). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/zfs-linux/+bug/1969482/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
