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From: "Alex Xu (Hello71)" <alex_y_xu@yahoo.ca>
To: Jens Axboe <axboe@kernel.dk>,
	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: very low IOPS due to "block: reduce kblockd_mod_delayed_work_on() CPU consumption"
Date: Sat, 18 Dec 2021 13:57:15 -0500	[thread overview]
Message-ID: <1639853092.524jxfaem2.none@localhost> (raw)
In-Reply-To: 1639853092.524jxfaem2.none.ref@localhost

Hi,

I recently noticed that between 6441998e2e and 9eaa88c703, I/O became 
much slower on my machine using ext4 on dm-crypt on NVMe with bfq 
scheduler. Checking iostat during heavy usage (find / -xdev and fstrim 
-v /), maximum IOPS had fallen from ~10000 to ~100. Reverting cb2ac2912a 
("block: reduce kblockd_mod_delayed_work_on() CPU consumption") resolves 
the issue.

Thanks,
Alex.

       reply	other threads:[~2021-12-18 18:57 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1639853092.524jxfaem2.none.ref@localhost>
2021-12-18 18:57 ` Alex Xu (Hello71) [this message]
2021-12-18 19:02   ` very low IOPS due to "block: reduce kblockd_mod_delayed_work_on() CPU consumption" Jens Axboe
2021-12-19 14:58     ` Jens Axboe
2021-12-19 15:28       ` Jens Axboe
2021-12-20  5:15         ` Dexuan Cui
2021-12-28  2:30           ` Yin Fengwei
2021-12-28 13:49             ` Oliver Sang
2022-01-22  6:14               ` Dexuan Cui
2022-02-08 18:34                 ` Dexuan Cui
2021-12-23 11:50         ` Christoph Hellwig

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