Hi, > On 4.02.21 г. 13:34 ч., Wang Yugui wrote: > > Hi, > > > >> On 4.02.21 г. 5:17 ч., Wang Yugui wrote: > >>> Hi, > >>> > >>> I tried to run btrfs misc-next(5.11-rc6 +81patches) based on linux LTS > >>> 5.10.12 with the same other kernel components and the same kernel config. > >>> > >>> Better dbench(sync open) result on both Throughput and max_latency. > >>> > >> > >> If i understand correctly you rebased current misc-next to 5.10.12, if > >> so this means there is something else in the main kernel, that's not > >> btrfs related which degrades performance, it seems you've got a 300ms > >> win by running on 5.10 as compared on 5.11-rc6-based misc next, is that > >> right? > > > > Yes. > > I just realized this could also be caused by btrfs code that has already > landed in v5.11-rc1 for example. I.e the main pull req for this release.
This performance problem seems very complex. result of btrfs 5.10.12 + these btrfs patchset + linux other kernel of 5.10.12 - 5.11 free-space-tree 13 patch - 5.11 btrfs: some performance improvements for dbench alike workloads - misc-next btrfs: more performance improvements for dbench workloads - misc-next Improve preemptive ENOSPC flushing Operation Count AvgLat MaxLat ---------------------------------------- NTCreateX 858500 0.030 2.969 Close 630548 0.002 0.071 Rename 36416 0.744 3.791 Unlink 173375 0.503 4.109 Qpathinfo 779355 0.014 2.715 Qfileinfo 136041 0.002 0.054 Qfsinfo 142728 0.004 0.084 Sfileinfo 69953 0.010 0.098 Find 301093 0.059 2.670 WriteX 424594 3.999 1765.527 ReadX 1348726 0.005 0.397 LockX 2816 0.004 0.022 UnlockX 2816 0.003 0.025 Flush 60094 0.764 1478.133 Throughput 445.83 MB/sec (sync open) 32 clients 32 procs max_latency=1765.539 ms still worse than btrfs misc-next(20210203) + linux other kernel of 5.10.12 Operation Count AvgLat MaxLat ---------------------------------------- NTCreateX 958611 0.026 440.564 Close 703418 0.002 0.085 Rename 40599 0.518 439.825 Unlink 194095 0.282 439.792 Qpathinfo 869295 0.010 1.852 Qfileinfo 151285 0.002 0.095 Qfsinfo 159492 0.004 0.051 Sfileinfo 78078 0.010 0.104 Find 335905 0.036 3.043 WriteX 473353 3.637 713.039 ReadX 1502197 0.005 0.752 LockX 3100 0.004 0.024 UnlockX 3100 0.002 0.020 Flush 67264 0.575 363.550 Throughput 497.551 MB/sec (sync open) 32 clients 32 procs max_latency=713.045 ms so there is some other patch in misc-next improved this performance too. but MaxLat/AvgLat of WriteX is still 175 in btrfs misc-next(20210203) + linux other kernel of 5.10.12, so there maybe some patch after 5.10 cause new performance problem too. Best Regards Wang Yugui (wangyu...@e16-tech.com) 2021/02/04 > > > > maybye some code rather than btrfs in main kernel 5.11.rc6 have degrades > > performance. > > or maybe just because of different kernel config. > > kernel config I used: > > https://kojipkgs.fedoraproject.org/packages/kernel/5.11.0/0.rc6.141.eln108/ > > https://kojipkgs.fedoraproject.org/packages/kernel/5.10.12/200.fc33/ > > > > I rebased current misc-next to 5.10.12, so that there is only diff in > > btrfs source code. > > > > only 3 minor patch needed for this rebase, there seems no broken kernel API > > change for btrfs between 5.10 and 5.11. > > # add-to-5.10 0001-block-add-a-bdev_kobj-helper.patch > > # drop-from-btrs-misc-next 0001-block-remove-i_bdev.patch > > # fix-to-btrfs-misc-next 0001-btrfs-bdev_nr_sectors.patch > > > > more patch come into misc-next today, they are yet not rebased/tested. > > > > Best Regards > > Wang Yugui (wangyu...@e16-tech.com) > > 2021/02/04 > >
