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Date:   Sun, 23 Jul 2023 19:35:47 +0200
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Subject: Re: [PATCH 6.4 800/800] io_uring: Use io_schedule* in cqring wait
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From:   "Linux regression tracking #update (Thorsten Leemhuis)" 
        <regressions@leemhuis.info>
To:     Oleksandr Natalenko <oleksandr@natalenko.name>,
        stable@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Pavel Begunkov <asml.silence@gmail.com>,
        io-uring@vger.kernel.org, linux-kernel@vger.kernel.org,
        Andres Freund <andres@anarazel.de>,
        Jens Axboe <axboe@kernel.dk>,
        Linux kernel regressions list <regressions@lists.linux.dev>
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          <regressions@lists.linux.dev>
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On 23.07.23 14:11, Linux regression tracking #adding (Thorsten Leemhuis)
wrote:
> On 23.07.23 11:39, Oleksandr Natalenko wrote:
>> On neděle 16. července 2023 21:50:53 CEST Greg Kroah-Hartman wrote:
>>> From: Andres Freund <andres@anarazel.de>
>>>
>>> commit 8a796565cec3601071cbbd27d6304e202019d014 upstream.
>>>
>>> I observed poor performance of io_uring compared to synchronous IO. That
>>> turns out to be caused by deeper CPU idle states entered with io_uring,
>>> due to io_uring using plain schedule(), whereas synchronous IO uses
>>> io_schedule().

> #regzbot introduced 8a796565cec360107 ^
> https://bbs.archlinux.org/viewtopic.php?id=287343
> https://bugzilla.kernel.org/show_bug.cgi?id=217700
> https://bugzilla.kernel.org/show_bug.cgi?id=217699
> #regzbot title block: io_uring: high iowait rates and stalls
> #regzbot ignore-activity

Apparently expected behavior:
https://lore.kernel.org/lkml/538065ee-4130-6a00-dcc8-f69fbc7d7ba0@kernel.dk/

#regzbot resolve: notabug: on a closer look it turned out that's
expected behavior

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
Everything you wanna know about Linux kernel regression tracking:
https://linux-regtracking.leemhuis.info/about/#tldr
That page also explains what to do if mails like this annoy you.

#regzbot ignore-activity