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Date:   Thu, 20 Apr 2023 09:55:40 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Andrew Theurer <atheurer@redhat.com>
Cc:     Marcelo Tosatti <mtosatti@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Lameter <cl@linux.com>,
        Aaron Tomlin <atomlin@atomlin.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Russell King <linux@armlinux.org.uk>,
        Huacai Chen <chenhuacai@kernel.org>,
        Heiko Carstens <hca@linux.ibm.com>, x86@kernel.org,
        Vlastimil Babka <vbabka@suse.cz>
Subject: Re: [PATCH v7 00/13] fold per-CPU vmstats remotely
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On Wed 19-04-23 08:44:23, Andrew Theurer wrote:
> > On Apr 19, 2023, at 6:15 AM, Marcelo Tosatti <mtosatti@redhat.com> wrote:
> >> Andrew Theurer, can you please explain what problem is the vmstat_work
> >> interruption causing in your testing?
> > 
> > +CC Andrew.
> 
> Nearly every telco we work with for 5G RAN is demanding <20 usec CPU
> latency as measured by cyclictest & oslat.  We cannot achieve under 20
> usec with the vmstats interruption.

Are you able to get those latency requirements with PREEMPT_RT?
-- 
Michal Hocko
SUSE Labs