From: Khalid Aziz <khalid.aziz@oracle.com>
To: Peter Zijlstra <peterz@infradead.org>, Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>,
"H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@kernel.org>,
akpm@linux-foundation.org, viro@zeniv.linux.org.uk,
oleg@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [RFC] [PATCH] Pre-emption control for userspace
Date: Wed, 05 Mar 2014 12:58:29 -0700 [thread overview]
Message-ID: <531781E5.8010000@oracle.com> (raw)
In-Reply-To: <20140305111006.GT9987@twins.programming.kicks-ass.net>
On 03/05/2014 04:10 AM, Peter Zijlstra wrote:
> On Tue, Mar 04, 2014 at 04:51:15PM -0800, Andi Kleen wrote:
>> Anything else?
>
> Proxy execution; its a form of PI that works for arbitrary scheduling
> policies (thus also very much including fair).
>
> With that what you effectively end up with is the lock holder running
> 'boosted' by the runtime of its blocked chain until the entire chain
> runs out of time, at which point preemption doesn't matter anyhow.
>
Hello Peter,
I read through the concept of proxy execution and it is a very
interesting concept. I come from many years of realtime and embeddded
systems development and I can easily recall various problems in the past
that can be solved or helped by this. Looking at the current problem I
am trying to solve with databases and JVM, I run into the same issue I
described in my earlier email. Proxy execution is a post-contention
solution. By the time proxy execution can do something for my case, I
have already paid the price of contention and a context switch which is
what I am trying to avoid. For a critical section that is very short
compared to the size of execution thread, which is the case I am looking
at, avoiding preemption in the middle of that short critical section
helps much more than dealing with lock contention later on. The goal
here is to avoid lock contention and associated cost. I do understand
the cost of dealing with lock contention poorly and that can easily be
much bigger cost, but I am looking into avoiding even getting there.
Thanks,
Khalid
next prev parent reply other threads:[~2014-03-05 19:59 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-03 18:07 [RFC] [PATCH] Pre-emption control for userspace Khalid Aziz
2014-03-03 21:51 ` Davidlohr Bueso
2014-03-03 23:29 ` Khalid Aziz
2014-03-04 13:56 ` Oleg Nesterov
2014-03-04 17:44 ` Khalid Aziz
2014-03-04 18:38 ` Al Viro
2014-03-04 19:01 ` Khalid Aziz
2014-03-04 19:03 ` Oleg Nesterov
2014-03-04 20:14 ` Khalid Aziz
2014-03-05 14:38 ` Oleg Nesterov
2014-03-05 16:12 ` Oleg Nesterov
2014-03-05 17:10 ` Khalid Aziz
2014-03-04 21:12 ` H. Peter Anvin
2014-03-04 21:39 ` Khalid Aziz
2014-03-04 22:23 ` One Thousand Gnomes
2014-03-04 22:44 ` Khalid Aziz
2014-03-05 0:39 ` Thomas Gleixner
2014-03-05 0:51 ` Andi Kleen
2014-03-05 11:10 ` Peter Zijlstra
2014-03-05 17:29 ` Khalid Aziz
2014-03-05 19:58 ` Khalid Aziz [this message]
2014-03-06 9:57 ` Peter Zijlstra
2014-03-06 16:08 ` Khalid Aziz
2014-03-06 11:14 ` Thomas Gleixner
2014-03-06 16:32 ` Khalid Aziz
2014-03-05 14:54 ` Oleg Nesterov
2014-03-05 15:56 ` Andi Kleen
2014-03-05 16:36 ` Oleg Nesterov
2014-03-05 17:22 ` Khalid Aziz
2014-03-05 23:13 ` David Lang
2014-03-05 23:48 ` Khalid Aziz
2014-03-05 23:56 ` H. Peter Anvin
2014-03-06 0:02 ` Khalid Aziz
2014-03-06 0:13 ` H. Peter Anvin
2014-03-05 23:59 ` David Lang
2014-03-06 0:17 ` Khalid Aziz
2014-03-06 0:36 ` David Lang
2014-03-06 1:22 ` Khalid Aziz
2014-03-06 14:23 ` David Lang
2014-03-06 12:13 ` Kevin Easton
2014-03-06 13:59 ` Peter Zijlstra
2014-03-06 22:41 ` Andi Kleen
2014-03-06 14:25 ` David Lang
2014-03-06 16:12 ` Khalid Aziz
2014-03-06 13:24 ` Rasmus Villemoes
2014-03-06 13:34 ` Peter Zijlstra
2014-03-06 13:45 ` Rasmus Villemoes
2014-03-06 14:02 ` Peter Zijlstra
2014-03-06 14:33 ` Thomas Gleixner
2014-03-06 14:34 ` H. Peter Anvin
2014-03-06 14:04 ` Thomas Gleixner
2014-03-25 17:17 ` [PATCH v2] " Khalid Aziz
2014-03-25 17:44 ` Andrew Morton
2014-03-25 17:56 ` Khalid Aziz
2014-03-25 18:14 ` Andrew Morton
2014-03-25 17:46 ` Oleg Nesterov
2014-03-25 17:59 ` Khalid Aziz
2014-03-25 18:20 ` Andi Kleen
2014-03-25 18:47 ` Khalid Aziz
2014-03-25 19:47 ` Andi Kleen
2014-03-25 18:59 ` Eric W. Biederman
2014-03-25 19:15 ` Khalid Aziz
2014-03-25 20:31 ` Eric W. Biederman
2014-03-25 21:37 ` Khalid Aziz
2014-03-26 6:03 ` Mike Galbraith
2014-03-25 23:01 ` [RFC] [PATCH] " Davidlohr Bueso
2014-03-25 23:29 ` Khalid Aziz
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