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Date:   Tue, 18 Apr 2023 19:21:51 +0800
From:   Aaron Lu <aaron.lu@intel.com>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
CC:     Peter Zijlstra <peterz@infradead.org>,
        <linux-kernel@vger.kernel.org>, Olivier Dion <odion@efficios.com>,
        <michael.christie@oracle.com>
Subject: Re: [RFC PATCH v8] sched: Fix performance regression introduced by
 mm_cid
Message-ID: <20230418112151.GA565498@ziqianlu-desk2>
References: <20230417150831.264780-1-mathieu.desnoyers@efficios.com>
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On Mon, Apr 17, 2023 at 11:08:31AM -0400, Mathieu Desnoyers wrote:
> Introduce per-mm/cpu current concurrency id (mm_cid) to fix a PostgreSQL
> sysbench regression reported by Aaron Lu.

For postgres_sysbench on SPR:
sched_mm_cid_migrate_to() is in the range of 0.1x% - 0.4x%, mm_cid_get()
is in the range of 0.1x% - 0.3x%. Other cid functions are pretty minor.

For hackbench on SPR:
ched_mm_cid_migrate_to() is about 3%-4%, mm_cid_get() is about 7%-8%,
other cid functions are pretty minor.

Thanks,
Aaron