Re: [PATCH v5 00/14] blk-mq: Reduce static requests memory footprint for shared sbitmap

[Jens Axboe]

On 10/5/21 7:34 AM, John Garry wrote:
> On 05/10/2021 13:35, Jens Axboe wrote:
>>> Baseline is 1b2d1439fc25 (block/for-next) Merge branch 'for-5.16/io_uring'
>>> into for-next
>> Let's get this queued up for testing, thanks John.
> 
> Cheers, appreciated
> 
> @Kashyap, You mentioned that when testing you saw a performance 
> regression from v5.11 -> v5.12 - any idea on that yet? Can you describe 
> the scenario, like IO scheduler and how many disks and the type? Does 
> disabling host_tagset_enable restore performance?

FWIW, I ran my usual peak testing on this and didn't observe any regressions.
Caveat being that a) no scheduler is involved, and b) no shared tags. But
at least that fast case/path is fine.

-- 
Jens Axboe