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Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 14 Feb 2022 07:39:17 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Imran Khan <imran.f.khan@oracle.com>
Cc:     gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 1/2] kernfs: use hashed mutex and spinlock in place of
 global ones.
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Hello,

On Mon, Feb 14, 2022 at 11:19:38PM +1100, Imran Khan wrote:
> > * How did you come up with the above numbers? Are they based on some
> >   experimentation? It'd be nice if the comment explains why the numbers are
> >   like that.
> > 
> 
> I did some testing using different number of CPUs with qemu and the
> above numbers were collected from there. It may not be optimum but this
> is what I could think of while doing those internal tests.
> 
> Do you think it may be better to make this configurable via Kconfig.

I think it's good as-is for now and it's super easy and cheap to increase
the hashtable size when some cases see a high contention.

Thanks.

-- 
tejun