Public bug reported: Related bug: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1657539
This issue was fixed in Zesty, but also impacts the Xenial and Yakkety kernels. Can you please pull this patch back to Xenial+? https://git.kernel.org/cgit/linux/kernel/git/axboe/linux- block.git/commit/?h=for-4.11/block&id=729204ef49ec00b788ce23deb9eb922a5769f55d author Ming Lei <ming....@canonical.com> 2016-12-17 10:49:09 (GMT) committer Jens Axboe <ax...@fb.com> 2017-01-12 03:47:08 (GMT) commit 729204ef49ec00b788ce23deb9eb922a5769f55d (patch) tree ab5cc3c0aa17fa8b988ed7dfefe888000fac0be3 parent 1661f2e21c8bbf922dcb76faf2126a33ffe4cddb (diff) block: relax check on sg gap If the last bvec of the 1st bio and the 1st bvec of the next bio are physically contigious, and the latter can be merged to last segment of the 1st bio, we should think they don't violate sg gap(or virt boundary) limit. Both Vitaly and Dexuan reported lots of unmergeable small bios are observed when running mkfs on Hyper-V virtual storage, and performance becomes quite low. This patch fixes that performance issue. The same issue should exist on NVMe, since it sets virt boundary too. Reported-by: Vitaly Kuznetsov <vkuzn...@redhat.com> Reported-by: Dexuan Cui <de...@microsoft.com> Tested-by: Dexuan Cui <de...@microsoft.com> Cc: Keith Busch <keith.bu...@intel.com> Signed-off-by: Ming Lei <ming....@canonical.com> Signed-off-by: Jens Axboe <ax...@fb.com> ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1682215 Title: [Hyper-V] mkfs regression in kernel 4.4+ To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1682215/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
