From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
To: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>,
"Waskiewicz Jr,
Peter P"
<peter.p.waskiewicz.jr-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Thomas Gleixner <tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>,
Ingo Molnar <mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>,
"containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org"
<containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>,
"cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
"linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: Re: [PATCH 0/4] x86: Add Cache QoS Monitoring (CQM) support
Date: Tue, 14 Jan 2014 09:58:26 -0800 [thread overview]
Message-ID: <52D57AC2.3090109@zytor.com> (raw)
In-Reply-To: <20140113075528.GR7572-RM5+C6weyIYnLiPH7yDmwOa11wxjtiyuLtmvbW2Dspo@public.gmane.org>
On 01/12/2014 11:55 PM, Peter Zijlstra wrote:
>
> The problem is, since there's a limited number of RMIDs we have to
> rotate at some point, but since changing RMIDs is nondeterministic we
> can't.
>
This is fundamentally the crux here. RMIDs are quite expensive for the
hardware to implement, so they are limited - but recycling them is
*very* expensive because you literally have to touch every line in the
cache.
-hpa
WARNING: multiple messages have this Message-ID (diff)
From: "H. Peter Anvin" <hpa@zytor.com>
To: Peter Zijlstra <peterz@infradead.org>,
"Waskiewicz Jr, Peter P" <peter.p.waskiewicz.jr@intel.com>
Cc: Tejun Heo <tj@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Li Zefan <lizefan@huawei.com>,
"containers@lists.linux-foundation.org"
<containers@lists.linux-foundation.org>,
"cgroups@vger.kernel.org" <cgroups@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/4] x86: Add Cache QoS Monitoring (CQM) support
Date: Tue, 14 Jan 2014 09:58:26 -0800 [thread overview]
Message-ID: <52D57AC2.3090109@zytor.com> (raw)
In-Reply-To: <20140113075528.GR7572@laptop.programming.kicks-ass.net>
On 01/12/2014 11:55 PM, Peter Zijlstra wrote:
>
> The problem is, since there's a limited number of RMIDs we have to
> rotate at some point, but since changing RMIDs is nondeterministic we
> can't.
>
This is fundamentally the crux here. RMIDs are quite expensive for the
hardware to implement, so they are limited - but recycling them is
*very* expensive because you literally have to touch every line in the
cache.
-hpa
next prev parent reply other threads:[~2014-01-14 17:58 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-03 20:34 [PATCH 0/4] x86: Add Cache QoS Monitoring (CQM) support Peter P Waskiewicz Jr
2014-01-03 20:34 ` Peter P Waskiewicz Jr
2014-01-03 20:34 ` [PATCH 1/4] x86: Add support for Cache QoS Monitoring (CQM) detection Peter P Waskiewicz Jr
2014-01-03 20:34 ` [PATCH 2/4] x86: Add Cache QoS Monitoring support to x86 perf uncore Peter P Waskiewicz Jr
[not found] ` <1388781285-18067-1-git-send-email-peter.p.waskiewicz.jr-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
2014-01-03 20:34 ` [PATCH 3/4] cgroup: Add new cacheqos cgroup subsys to support Cache QoS Monitoring Peter P Waskiewicz Jr
2014-01-03 20:34 ` Peter P Waskiewicz Jr
2014-01-03 20:34 ` [PATCH 4/4] Documentation: Add documentation for cacheqos cgroup Peter P Waskiewicz Jr
2014-01-03 20:34 ` Peter P Waskiewicz Jr
2014-01-04 16:10 ` [PATCH 0/4] x86: Add Cache QoS Monitoring (CQM) support Tejun Heo
2014-01-04 16:10 ` Tejun Heo
2014-01-04 16:10 ` Tejun Heo
[not found] ` <20140104161050.GA24306-Gd/HAXX7CRxy/B6EtB590w@public.gmane.org>
2014-01-04 22:43 ` Waskiewicz Jr, Peter P
2014-01-04 22:43 ` Waskiewicz Jr, Peter P
[not found] ` <1388875369.9761.25.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-04 22:50 ` Tejun Heo
2014-01-04 22:50 ` Tejun Heo
[not found] ` <20140104225058.GC24306-Gd/HAXX7CRxy/B6EtB590w@public.gmane.org>
2014-01-05 5:23 ` Waskiewicz Jr, Peter P
2014-01-05 5:23 ` Waskiewicz Jr, Peter P
[not found] ` <1388899376.9761.45.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-06 11:16 ` Peter Zijlstra
2014-01-06 11:16 ` Peter Zijlstra
[not found] ` <20140106111624.GB5623-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 16:34 ` Waskiewicz Jr, Peter P
2014-01-06 16:34 ` Waskiewicz Jr, Peter P
[not found] ` <1389026035.32504.3.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-06 16:41 ` Peter Zijlstra
2014-01-06 16:41 ` Peter Zijlstra
[not found] ` <20140106164150.GQ31570-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 16:47 ` Waskiewicz Jr, Peter P
2014-01-06 16:47 ` Waskiewicz Jr, Peter P
[not found] ` <1389026867.32504.16.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-06 17:53 ` Peter Zijlstra
2014-01-06 17:53 ` Peter Zijlstra
[not found] ` <20140106175338.GF30183-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 18:05 ` Waskiewicz Jr, Peter P
2014-01-06 18:05 ` Waskiewicz Jr, Peter P
2014-01-06 18:06 ` Peter Zijlstra
2014-01-06 18:06 ` Peter Zijlstra
[not found] ` <20140106180636.GG30183-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 20:10 ` Waskiewicz Jr, Peter P
2014-01-06 20:10 ` Waskiewicz Jr, Peter P
[not found] ` <1389039035.32504.35.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-06 21:26 ` Peter Zijlstra
2014-01-06 21:26 ` Peter Zijlstra
2014-01-06 21:26 ` Peter Zijlstra
[not found] ` <20140106212623.GH30183-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 21:48 ` Waskiewicz Jr, Peter P
2014-01-06 21:48 ` Waskiewicz Jr, Peter P
[not found] ` <1389044899.32504.43.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-06 22:12 ` Peter Zijlstra
2014-01-06 22:12 ` Peter Zijlstra
[not found] ` <20140106221251.GJ30183-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 22:45 ` Waskiewicz Jr, Peter P
2014-01-06 22:45 ` Waskiewicz Jr, Peter P
[not found] ` <1389048315.32504.57.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-07 8:34 ` Peter Zijlstra
2014-01-07 8:34 ` Peter Zijlstra
[not found] ` <20140107083440.GL30183-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-07 15:15 ` Waskiewicz Jr, Peter P
2014-01-07 15:15 ` Waskiewicz Jr, Peter P
[not found] ` <1389107743.32504.69.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-07 21:12 ` Peter Zijlstra
2014-01-07 21:12 ` Peter Zijlstra
[not found] ` <20140107211229.GF2480-RM5+C6weyIYnLiPH7yDmwOa11wxjtiyuLtmvbW2Dspo@public.gmane.org>
2014-01-10 18:55 ` Waskiewicz Jr, Peter P
2014-01-10 18:55 ` Waskiewicz Jr, Peter P
[not found] ` <1389380100.32504.172.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-01-13 7:55 ` Peter Zijlstra
2014-01-13 7:55 ` Peter Zijlstra
[not found] ` <20140113075528.GR7572-RM5+C6weyIYnLiPH7yDmwOa11wxjtiyuLtmvbW2Dspo@public.gmane.org>
2014-01-14 17:58 ` H. Peter Anvin
2014-01-14 17:58 ` H. Peter Anvin [this message]
2014-01-14 17:58 ` H. Peter Anvin
[not found] ` <52D57AC2.3090109-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
2014-01-27 17:34 ` Peter Zijlstra
2014-01-27 17:34 ` Peter Zijlstra
[not found] ` <20140127173420.GA9636-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-02-18 17:29 ` Waskiewicz Jr, Peter P
2014-02-18 17:29 ` Waskiewicz Jr, Peter P
[not found] ` <1392744567.3069.42.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-02-18 19:35 ` Peter Zijlstra
2014-02-18 19:35 ` Peter Zijlstra
2014-02-18 19:35 ` Peter Zijlstra
[not found] ` <20140218193528.GQ14089-RM5+C6weyIYnLiPH7yDmwOa11wxjtiyuLtmvbW2Dspo@public.gmane.org>
2014-02-18 19:54 ` Waskiewicz Jr, Peter P
2014-02-18 19:54 ` Waskiewicz Jr, Peter P
[not found] ` <1392753259.607.9.camel-29DAm2eTeB2q+SSgkFU3IPooFf0ArEBIu+b9c/7xato@public.gmane.org>
2014-02-20 16:58 ` Peter Zijlstra
2014-02-20 16:58 ` Peter Zijlstra
2014-01-14 20:46 ` Waskiewicz Jr, Peter P
2014-01-14 20:46 ` Waskiewicz Jr, Peter P
2014-01-14 20:46 ` Waskiewicz Jr, Peter P
2014-01-06 16:47 ` Waskiewicz Jr, Peter P
2014-01-06 11:08 ` Peter Zijlstra
2014-01-06 11:08 ` Peter Zijlstra
[not found] ` <20140106110803.GA5623-ndre7Fmf5hadTX5a5knrm8zTDFooKrT+cvkQGrU6aU0@public.gmane.org>
2014-01-06 16:42 ` Waskiewicz Jr, Peter P
2014-01-06 16:42 ` Waskiewicz Jr, Peter P
2014-01-06 16:42 ` Waskiewicz Jr, Peter P
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