Re: [PATCH block-5.18] Revert "block: inherit request start time from bio for BLK_CGROUP"
From: Jens Axboe
Date: Wed Apr 27 2022 - 15:51:56 EST
On Wed, 27 Apr 2022 09:49:12 -1000, Tejun Heo wrote:
> This reverts commit 0006707723233cb2a9a23ca19fc3d0864835704c. It has a
> couple problems:
>
> * bio_issue_time() is stored in bio->bi_issue truncated to 51 bits. This
> overflows in slightly over 26 days. Setting rq->io_start_time_ns with it
> means that io duration calculation would yield >26days after 26 days of
> uptime. This, for example, confuses kyber making it cause high IO
> latencies.
>
> [...]
Applied, thanks!
[1/1] Revert "block: inherit request start time from bio for BLK_CGROUP"
commit: 4cddeacad6d4b23493a108d0705e7d2ab89ba5a3
Best regards,
--
Jens Axboe