This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed- xenial' to 'verification-done-xenial'. If the problem still exists, change the tag 'verification-needed-xenial' to 'verification-failed- xenial'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-xenial -- 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/1772412 Title: zfs 0.7.9 fixes a bug (https://github.com/zfsonlinux/zfs/pull/7343) that hangs the system completely Status in linux package in Ubuntu: Invalid Status in zfs-linux package in Ubuntu: Fix Released Status in linux source package in Bionic: Fix Released Status in zfs-linux source package in Bionic: Fix Released Bug description: SRU Bionic == SRU Justification == Intensive I/O such as performed by ZFS send/receive can cause hangs because of monopolization of the global system_taskq. The outcome is that z_zvol hung tasks occur and I/O gets blocked. == Fix == Upstream ZFS commit 77d8a0f1a4d0b2f59cee63088f7987cb38e66538 ("Fix hung z_zvol tasks during 'zfs receive'") fixes this issue, it adds a dedicated per-pool prefetch taskq that prevents the traverse code from monopolizing the global (and limited) system_taskq by inappropriately scheduling long running tasks on it. This fixes the z_zvol hung tasks. A trivial backport is required for Bionic ZFS. == Testcase == Perform large send/receives. Occasionally they lock up. With the fix, this issue is addressed and no more lockups occur. Also must pass the full ZFS ubuntu autotest tests to prove no regressions occur. == Regression Potential == This fix adds more per-pool prefetch taskq's so we have more kernel resources being used. There is therefore a very small risk that this may impact ZFS running on memory and CPU constrained systems. However, the fix is small, has been upstream for a while and is in Cosmic+ releases and has not caused any regressions, so I think this is a relatively safe fix. ------ I have experienced the problems fixed by this commit https://github.com/zfsonlinux/zfs/pull/7343 a few times on my NAS. The system hangs completely when it occurs. It looks like 0.7.9 brings other interesting bug fixes that potentially freeze the system. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1772412/+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
