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Date:   Mon, 11 Jan 2021 16:27:20 -0800
From:   Roman Gushchin <guro@fb.com>
To:     Jann Horn <jannh@google.com>
CC:     Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux-MM <linux-mm@kvack.org>,
        kernel list <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shakeel Butt <shakeelb@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Minchan Kim <minchan@kernel.org>
Subject: Re: SLUB: percpu partial object count is highly inaccurate, causing
 some memory wastage and maybe also worse tail latencies?
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On Tue, Jan 12, 2021 at 12:12:47AM +0100, Jann Horn wrote:
> [This is not something I intend to work on myself. But since I
> stumbled over this issue, I figured I should at least document/report
> it, in case anyone is willing to pick it up.]

Hi, Jann!

Thank you very much for this report!

It should be less of a problem since 5.9, but still on a machine with
many CPUs a non-trivial amount of memory is wasted.

I'll definitely take a look.

Thanks!