| Message ID | cover.1685900733.git.ritesh.list@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | iomap: Add support for per-block dirty state to improve write performance | expand |
Ritesh, Am Mo., 5. Juni 2023 um 03:33 Uhr schrieb Ritesh Harjani (IBM) <ritesh.list@gmail.com>: > Hello All, > > Please find PATCHv6 which adds per-block dirty tracking to iomap. > As discussed earlier this is required to improve write performance and reduce > write amplification for cases where either blocksize is less than pagesize (such > as Power platform with 64k pagesize) or when we have a large folio (such as xfs > which currently supports large folio). > > RFCv5 -> PATCHv6: > ================= > 1. Addresses review comments from Brian, Christoph and Matthew. > @Christoph: > - I have renamed the higher level functions such as iop_alloc/iop_free() to > iomap_iop_alloc/free() in v6. > - As for the low level bitmap accessor functions I couldn't find any better > naming then iop_test_/set/clear_**. I could have gone for > iomap_iop__test/set/clear/_** or iomap__iop_test/set/clear_**, but > I wasn't convinced with either of above as it also increases function > name. > Besides iop_test/set_clear_ accessors functions for uptodate and dirty > status tracking make sense as we are sure we have a valid iop in such > cases. Please do let me know if this looks ok to you. > 2. I tried testing gfs2 (initially with no patches) with xfstests. But I always ended up > in some or the other deadlock (I couldn't spend any time debugging that). > I also ran it with -x log, but still it was always failing for me. > @Andreas: > - could you please suggest how can I test gfs2 with these patches. I see gfs2 > can have a smaller blocksize and it uses iomap buffered io path. It will be > good if we can get these patches tested on it too. here's a minimal list of tests we're running automatically on a daily basis: https://gitlab.com/redhat/centos-stream/tests/kernel/kernel-tests/-/blob/main/filesystems/xfs/xfstests/RUNTESTS.gfs2 Please note that function inode_to_wb() in <linux/backing-dev.h> includes some asserts that are active when CONFIG_LOCKDEP is enabled. Those asserts will cause every single fstest to fail. So either disable CONFIG_LOCKDEP or remove the asserts in inode_to_wb() for now. Thanks, Andreas > 3. I can now say I have run some good amount of fstests on these patches on > these platforms and I haven't found any new failure in my testing so far. > arm64 (64k pagesize): with 4k -g quick > Power: with 4k -g auto > x86: 1k, 4k with -g auto and adv_auto > > From my testing so far these patches looks stable to me and if this looks good > to reviewers as well, do you think this can be queued to linux-next for wider > testing? > > Performance numbers copied from last patch commit message > ================================================== > Performance testing of below fio workload reveals ~16x performance > improvement using nvme with XFS (4k blocksize) on Power (64K pagesize) > FIO reported write bw scores improved from around ~28 MBps to ~452 MBps. > > 1. <test_randwrite.fio> > [global] > ioengine=psync > rw=randwrite > overwrite=1 > pre_read=1 > direct=0 > bs=4k > size=1G > dir=./ > numjobs=8 > fdatasync=1 > runtime=60 > iodepth=64 > group_reporting=1 > > [fio-run] > > 2. Also our internal performance team reported that this patch improves > their database workload performance by around ~83% (with XFS on Power) > > Ritesh Harjani (IBM) (5): > iomap: Rename iomap_page_create/release() to iomap_iop_alloc/free() > iomap: Move folio_detach_private() in iomap_iop_free() to the end > iomap: Refactor some iop related accessor functions > iomap: Allocate iop in ->write_begin() early > iomap: Add per-block dirty state tracking to improve performance > > fs/gfs2/aops.c | 2 +- > fs/iomap/buffered-io.c | 309 ++++++++++++++++++++++++++++++----------- > fs/xfs/xfs_aops.c | 2 +- > fs/zonefs/file.c | 2 +- > include/linux/iomap.h | 1 + > 5 files changed, 235 insertions(+), 81 deletions(-) > > -- > 2.40.1 >
Hello All, Please find PATCHv6 which adds per-block dirty tracking to iomap. As discussed earlier this is required to improve write performance and reduce write amplification for cases where either blocksize is less than pagesize (such as Power platform with 64k pagesize) or when we have a large folio (such as xfs which currently supports large folio). RFCv5 -> PATCHv6: ================= 1. Addresses review comments from Brian, Christoph and Matthew. @Christoph: - I have renamed the higher level functions such as iop_alloc/iop_free() to iomap_iop_alloc/free() in v6. - As for the low level bitmap accessor functions I couldn't find any better naming then iop_test_/set/clear_**. I could have gone for iomap_iop__test/set/clear/_** or iomap__iop_test/set/clear_**, but I wasn't convinced with either of above as it also increases function name. Besides iop_test/set_clear_ accessors functions for uptodate and dirty status tracking make sense as we are sure we have a valid iop in such cases. Please do let me know if this looks ok to you. 2. I tried testing gfs2 (initially with no patches) with xfstests. But I always ended up in some or the other deadlock (I couldn't spend any time debugging that). I also ran it with -x log, but still it was always failing for me. @Andreas: - could you please suggest how can I test gfs2 with these patches. I see gfs2 can have a smaller blocksize and it uses iomap buffered io path. It will be good if we can get these patches tested on it too. 3. I can now say I have run some good amount of fstests on these patches on these platforms and I haven't found any new failure in my testing so far. arm64 (64k pagesize): with 4k -g quick Power: with 4k -g auto x86: 1k, 4k with -g auto and adv_auto From my testing so far these patches looks stable to me and if this looks good to reviewers as well, do you think this can be queued to linux-next for wider testing? Performance numbers copied from last patch commit message ================================================== Performance testing of below fio workload reveals ~16x performance improvement using nvme with XFS (4k blocksize) on Power (64K pagesize) FIO reported write bw scores improved from around ~28 MBps to ~452 MBps. 1. <test_randwrite.fio> [global] ioengine=psync rw=randwrite overwrite=1 pre_read=1 direct=0 bs=4k size=1G dir=./ numjobs=8 fdatasync=1 runtime=60 iodepth=64 group_reporting=1 [fio-run] 2. Also our internal performance team reported that this patch improves their database workload performance by around ~83% (with XFS on Power) Ritesh Harjani (IBM) (5): iomap: Rename iomap_page_create/release() to iomap_iop_alloc/free() iomap: Move folio_detach_private() in iomap_iop_free() to the end iomap: Refactor some iop related accessor functions iomap: Allocate iop in ->write_begin() early iomap: Add per-block dirty state tracking to improve performance fs/gfs2/aops.c | 2 +- fs/iomap/buffered-io.c | 309 ++++++++++++++++++++++++++++++----------- fs/xfs/xfs_aops.c | 2 +- fs/zonefs/file.c | 2 +- include/linux/iomap.h | 1 + 5 files changed, 235 insertions(+), 81 deletions(-) -- 2.40.1