Public bug reported: In an upgrade from Jammy kernel 5.15.0-27-generic to 5.15.0-35-generic on x86_64 (AMD threadripper pro 39x5wx series), a 40x performance regression in the first read of cached writes to an encrypted dataset revealed that zfs is no longer configured to choose any implementations from advanced instruction sets:
$ grep . /sys/module/icp/parameters/*impl* /sys/module/icp/parameters/icp_aes_impl:cycle [fastest] generic x86_64 /sys/module/icp/parameters/icp_gcm_impl:cycle [fastest] generic With correct configuration, the output should read as follows: $ grep . /sys/module/icp/parameters/*impl* /sys/module/icp/parameters/icp_aes_impl:cycle [fastest] generic x86_64 aesni /sys/module/icp/parameters/icp_gcm_impl:cycle [fastest] avx generic pclmulqdq The immediate ill effects are the use of gcm_generic_mul instead of the dedicated instruction, consuming 50% CPU and slowing reads of data cached in ram to less than 20% of what they would be even reading directly from disk. openzfs changed its configure process to detect cpu features differently recently to adapt to the kernel api change. It seems that the upstream changes that unexport the needed symbols and the downstream changes in openzfs that stop using them were not cherrypicked in sync. https://github.com/openzfs/zfs/pull/13147 https://github.com/openzfs/zfs/pull/13236 ** Affects: zfs-linux (Ubuntu) Importance: Undecided Status: New -- 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/1977699 Title: zfs icp has deselected all optimized aes & gcm impls Status in zfs-linux package in Ubuntu: New Bug description: In an upgrade from Jammy kernel 5.15.0-27-generic to 5.15.0-35-generic on x86_64 (AMD threadripper pro 39x5wx series), a 40x performance regression in the first read of cached writes to an encrypted dataset revealed that zfs is no longer configured to choose any implementations from advanced instruction sets: $ grep . /sys/module/icp/parameters/*impl* /sys/module/icp/parameters/icp_aes_impl:cycle [fastest] generic x86_64 /sys/module/icp/parameters/icp_gcm_impl:cycle [fastest] generic With correct configuration, the output should read as follows: $ grep . /sys/module/icp/parameters/*impl* /sys/module/icp/parameters/icp_aes_impl:cycle [fastest] generic x86_64 aesni /sys/module/icp/parameters/icp_gcm_impl:cycle [fastest] avx generic pclmulqdq The immediate ill effects are the use of gcm_generic_mul instead of the dedicated instruction, consuming 50% CPU and slowing reads of data cached in ram to less than 20% of what they would be even reading directly from disk. openzfs changed its configure process to detect cpu features differently recently to adapt to the kernel api change. It seems that the upstream changes that unexport the needed symbols and the downstream changes in openzfs that stop using them were not cherrypicked in sync. https://github.com/openzfs/zfs/pull/13147 https://github.com/openzfs/zfs/pull/13236 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/zfs-linux/+bug/1977699/+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
