Public bug reported: [Impact] Read performance is ~9% slower than it could be, as measured by the iozone3 benchmark.
[Test Case] iozone -a I suggest collecting 5 runs of this, with and without the patch, and generating a report using: https://github.com/Rovanion/iozone-results-comparator/wiki/Overview [Fix] Apply a patch queued in the scsi tree that pre-allocates DMA slot buffers. [Regression Risk] As called out in the commit log, the trade-off here is static memory usage, which could grow by ~17MB. However, as also noted, this method actually uses *less* memory than the baseline when all slots are allocated (32MB). (Ubuntu uses a 4K kernel). The required fixes are localized to the hisi_sas driver. This driver is only used by two platforms supported by Ubuntu: HiSilicon D05 and HiSilicon D06. We will directly verify these fixes on those platforms. ** Affects: linux (Ubuntu) Importance: Undecided Assignee: dann frazier (dannf) Status: In Progress ** Affects: linux (Ubuntu Bionic) Importance: Undecided Assignee: dann frazier (dannf) Status: In Progress ** Also affects: linux (Ubuntu Bionic) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Bionic) Status: New => In Progress ** Changed in: linux (Ubuntu Bionic) Assignee: (unassigned) => dann frazier (dannf) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1777727 Title: hisi_sas: improve read performance by pre-allocating slot DMA buffers To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1777727/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
