Date:   Thu, 23 Dec 2021 03:50:23 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>,
        linux-block@vger.kernel.org, Dexuan Cui <decui@microsoft.com>,
        ming.lei@redhat.com, hch@lst.de, Long Li <longli@microsoft.com>,
        "Michael Kelley (LINUX)" <mikelley@microsoft.com>,
        linux-kernel@vger.kernel.org
Subject: Re: very low IOPS due to "block: reduce
 kblockd_mod_delayed_work_on() CPU consumption"
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On Sun, Dec 19, 2021 at 08:28:18AM -0700, Jens Axboe wrote:
> > 
> > Dexuan, can you test this for your test case too? I'm going to queue
> > up a revert for -rc6 just in case.
> 
> This one should be better...

We might just want something like a revert of
9f993737906b30d7b2454a38637d1f70ffd60f2f.

Or just always use a normal work queue for run_work, and then use a
timer to schedule it for the relatively rare delayed case.