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.
>
> 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
>
