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Date:   Mon, 22 Oct 2018 19:06:04 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Steve Sistare <steven.sistare@oracle.com>
Cc:     mingo@redhat.com, subhra.mazumdar@oracle.com,
        dhaval.giani@oracle.com, rohit.k.jain@oracle.com,
        daniel.m.jordan@oracle.com, pavel.tatashin@microsoft.com,
        matt@codeblueprint.co.uk, umgwanakikbuti@gmail.com,
        riel@redhat.com, jbacik@fb.com, juri.lelli@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 09/10] sched/fair: disable stealing if too many NUMA nodes
Message-ID: <20181022170604.GG3117@worktop.programming.kicks-ass.net>
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On Mon, Oct 22, 2018 at 07:59:40AM -0700, Steve Sistare wrote:
> The STEAL feature causes regressions on hackbench on larger NUMA systems,
> so disable it on systems with more than sched_steal_node_limit nodes
> (default 2).

How come? From a quick read the stealing is per LLC, where do we steal
across nodes?