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Date:   Sat, 7 Jan 2023 02:07:38 +0800
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Subject: Re: [External] Re: [PATCH v3] blk-throtl: Introduce sync and async
 queues for blk-throtl
To:     Tejun Heo <tj@kernel.org>, Jan Kara <jack@suse.cz>
Cc:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>,
        josef@toxicpanda.com, axboe@kernel.dk, cgroups@vger.kernel.org,
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        yinxin.x@bytedance.com
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在 2023/1/7 上午12:58, Tejun Heo 写道:

> 
> Jinke, is the case you described in the original email what you actually saw
> in production or a simplified test case for demonstration? If the latter,
> can you describe actual problems seen in production?
> 
> Thanks.
> 

Hi

In our internal scenario, iocost has been deployed as the main io 
isolation method and is gradually spreading。

But for some specific scenarios with old kernel versions, blk-throtl
is alose needed. The scenario described in my email is in the early 
stage of research and extensive testing for it. During this period，some 
priority inversion issues amoug cgroups or within one cgroup have been 
observed. So I send this patch to try to fix or mitigate some of these 
issues.

Thanks

Jinke