From: Matthew Wilcox <matthew@wil.cx>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Arjan van de Ven <arjan@infradead.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Prevent users from disabling tickless
Date: Tue, 21 Dec 2010 17:24:07 -0700 [thread overview]
Message-ID: <20101222002407.GM1263@parisc-linux.org> (raw)
In-Reply-To: <201012220046.23759.rjw@sisk.pl>
On Wed, Dec 22, 2010 at 12:46:23AM +0100, Rafael J. Wysocki wrote:
> On Wednesday, December 22, 2010, Matthew Wilcox wrote:
> >
> > Disabling NO_HZ has a serious negative effect on performance -- an extra
> > 70us per I/O. Prevent users from deselecting it.
> >
> > Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
>
> OTOH, it causes some systems to not work at all still. Sadly.
It doesn't stop people from specifying nohz=off on the kernel command line.
--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."
next prev parent reply other threads:[~2010-12-22 0:24 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-21 23:39 [PATCH] Prevent users from disabling tickless Matthew Wilcox
2010-12-21 23:46 ` Rafael J. Wysocki
2010-12-22 0:24 ` Matthew Wilcox [this message]
2010-12-22 0:38 ` Rafael J. Wysocki
2010-12-22 21:00 ` Frank Rowand
2010-12-22 21:34 ` Matthew Wilcox
2010-12-22 22:32 ` Frank Rowand
2010-12-26 22:22 ` Len Brown
2010-12-26 23:20 ` Grant Coady
2010-12-26 23:23 ` Regarding kernel work queue issues Raj Kumar
2010-12-25 15:42 ` [PATCH] Prevent users from disabling tickless Stefan Richter
2011-01-02 8:57 ` Pavel Machek
2011-01-02 9:15 ` Eric Dumazet
2011-01-02 10:59 ` Serge Belyshev
2011-01-02 11:06 ` Remy Bohmer
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