netdev - Re: Performance drop due to alloc_workqueue() misuse and recent change

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Message-ID: <ZYKUc7MUGvre2lGQ@slm.duckdns.org>
Date: Tue, 19 Dec 2023 21:14:59 -1000
From: Tejun Heo <tj@...nel.org>
To: Naohiro Aota <Naohiro.Aota@....com>
Cc: Lai Jiangshan <jiangshanlai@...il.com>,
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Subject: Re: Performance drop due to alloc_workqueue() misuse and recent
 change

Hello, again.

On Mon, Dec 04, 2023 at 04:03:47PM +0000, Naohiro Aota wrote:
...
> In summary, we misuse max_active, considering it is a global limit. And,
> the recent commit introduced a huge performance drop in some cases.  We
> need to review alloc_workqueue() usage to check if its max_active setting
> is proper or not.

Can you please test the following branch?

 https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git unbound-system-wide-max_active

Thanks.

-- 
tejun