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Date:   Sat, 8 Feb 2020 21:41:49 +0000 (UTC)
From:   Christopher Lameter <cl@linux.com>
To:     Wen Yang <wenyang@linux.alibaba.com>
cc:     Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Xunlei Pang <xlpang@linux.alibaba.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/slub: Detach node lock from counting free objects
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On Sat, 8 Feb 2020, Wen Yang wrote:

> I would greatly appreciate it if you kindly give me some feedback on this
> patch.

I think the measure is too severe given its use and the general impact on code.

Maybe avoid taking the lock or reducing the time a lock is taken when reading /proc/slabinfo is
the best approach?

Also you could cache the value in the userspace application? Why is this
value read continually?