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From: Peter Zijlstra <peterz@infradead.org>
To: Jon Maloy <jon.maloy@ericsson.com>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"mingo@kernel.org" <mingo@kernel.org>,
	"David Miller (davem@davemloft.net)" <davem@davemloft.net>
Subject: Re: Serious performance degradation in Linux 4.15
Date: Sat, 10 Feb 2018 15:01:17 +0100	[thread overview]
Message-ID: <20180210140117.GP25201@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <BN6PR15MB1553DFF82A45A4E532B6DC119AF20@BN6PR15MB1553.namprd15.prod.outlook.com>

On Fri, Feb 09, 2018 at 05:59:12PM +0000, Jon Maloy wrote:
> The two commits 
> d153b153446f7 (" sched/core: Fix wake_affine() performance regression") and
> f2cdd9cc6c97 ("sched/core: Address more wake_affine() regressions")
> are causing a serious performance degradation in Linux 4.5.
> 
> The effect is worst on TIPC, but even TCP is affected, as the figures below show. 

I did run a whole bunch of netperf and didn't see anything like that.
0-day also didn't report anything, and it too runs netperf.

I'll try and see if I can reproduce somewhere next week.

  reply	other threads:[~2018-02-10 14:01 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-09 17:59 Serious performance degradation in Linux 4.15 Jon Maloy
2018-02-10 14:01 ` Peter Zijlstra [this message]
2018-02-12 15:16 ` Peter Zijlstra
2018-02-13  8:14   ` Jon Maloy
2018-02-14 22:46   ` Matt Fleming
2018-02-15  8:38     ` Peter Zijlstra
2018-02-16 10:09     ` Peter Zijlstra
2018-02-16 10:17     ` Peter Zijlstra
2018-02-16 10:49       ` Mel Gorman
2018-02-16 14:38     ` Matt Fleming
2018-02-16 16:48       ` Peter Zijlstra

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