From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-f176.google.com (mail-ie0-f176.google.com [209.85.223.176]) by kanga.kvack.org (Postfix) with ESMTP id C8A566B0071 for ; Wed, 3 Dec 2014 10:32:03 -0500 (EST) Received: by mail-ie0-f176.google.com with SMTP id tr6so13394115ieb.7 for ; Wed, 03 Dec 2014 07:32:03 -0800 (PST) Received: from resqmta-po-04v.sys.comcast.net (resqmta-po-04v.sys.comcast.net. [2001:558:fe16:19:96:114:154:163]) by mx.google.com with ESMTPS id dz2si16701356igb.11.2014.12.03.07.32.02 for (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Wed, 03 Dec 2014 07:32:02 -0800 (PST) Date: Wed, 3 Dec 2014 09:32:00 -0600 (CST) From: Christoph Lameter Subject: Re: [Lsf-pc] [LSF/MM ATTEND] Expanding OS noise suppression In-Reply-To: <547E680F.4080108@amacapital.net> Message-ID: References: <547CA12A.6010102@redhat.com> <547E680F.4080108@amacapital.net> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: Rik van Riel , lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, "Paul E. McKenney" , Frederic Weisbecker On Tue, 2 Dec 2014, Andy Lutomirski wrote: > FWIW, context tracking for full nohz is *slow*, so it may reduce noise, > but it dramatically increases syscall and fault overhead. This isn't > really an mm issue, though. In general though no syscalls are performed in critical latency sensitive segments and the I/O is done using kernel bypass. So controlling the OS causing hiccups becomes an important issue. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org