From: "Luck, Tony" <tony.luck@intel.com>
To: "Tang, Feng" <feng.tang@intel.com>, Borislav Petkov <bp@suse.de>
Cc: "Chen, Rong A" <rong.a.chen@intel.com>,
LKML <linux-kernel@vger.kernel.org>,
"lkp@lists.01.org" <lkp@lists.01.org>,
"Mel Gorman" <mgorman@suse.com>
Subject: RE: [LKP] Re: [x86/mce] 1de08dccd3: will-it-scale.per_process_ops -14.1% regression
Date: Tue, 25 Aug 2020 16:44:37 +0000 [thread overview]
Message-ID: <b704f3c6298f46abbc59105ec0d52d14@intel.com> (raw)
In-Reply-To: <20200825062305.GA83850@shbuild999.sh.intel.com>
> These 2 variables are accessed in 2 hot call stacks (for this 288 CPU
> Xeon Phi platform):
This might be the key element of "weirdness" for this system. It
has 288 CPUs ... cache alignment problems are often not too bad
on "small" systems. The as you scale up to bigger machines you
suddenly hit some critical point and performance drops dramatically.
It's good that you are picking up tips on how to bisect these and diagnose
the underlying problem. Number of cores is going to keep increasing, so
we will keep finding new issues like this.
-Tony
next prev parent reply other threads:[~2020-08-25 16:45 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-25 11:44 [x86/mce] 1de08dccd3: will-it-scale.per_process_ops -14.1% regression kernel test robot
2020-04-25 13:01 ` Borislav Petkov
2020-08-18 8:29 ` [LKP] " Feng Tang
2020-08-18 20:06 ` Luck, Tony
2020-08-19 2:04 ` Feng Tang
2020-08-19 2:23 ` Luck, Tony
2020-08-19 3:04 ` Feng Tang
2020-08-19 3:15 ` Feng Tang
2020-08-21 2:02 ` Feng Tang
2020-08-24 15:14 ` Borislav Petkov
2020-08-24 15:33 ` Feng Tang
2020-08-24 15:38 ` Luck, Tony
2020-08-24 15:48 ` Feng Tang
2020-08-24 16:12 ` Borislav Petkov
2020-08-24 16:56 ` Mel Gorman
2020-08-25 6:49 ` Feng Tang
2020-08-25 6:23 ` Feng Tang
2020-08-25 16:44 ` Luck, Tony [this message]
2020-08-26 1:45 ` Feng Tang
2020-08-28 17:48 ` Borislav Petkov
2020-08-31 2:16 ` Feng Tang
2020-08-31 7:56 ` Mel Gorman
2020-08-31 8:23 ` Feng Tang
2020-08-31 8:55 ` Mel Gorman
2020-08-31 12:53 ` Feng Tang
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