Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754057Ab0KSNB0 (ORCPT ); Fri, 19 Nov 2010 08:01:26 -0500 Received: from casper.infradead.org ([85.118.1.10]:44484 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243Ab0KSNBZ convert rfc822-to-8bit (ORCPT ); Fri, 19 Nov 2010 08:01:25 -0500 Subject: Re: [RFC/RFT PATCH v3] sched: automated per tty task groups From: Peter Zijlstra To: Mathieu Desnoyers Cc: Samuel Thibault , Mike Galbraith , Hans-Peter Jansen , linux-kernel@vger.kernel.org, Lennart Poettering , Linus Torvalds , david@lang.hm, Dhaval Giani , Vivek Goyal , Oleg Nesterov , Markus Trippelsdorf , Ingo Molnar , Balbir Singh In-Reply-To: <20101119125548.GC24411@Krystal> References: <1289916171.5169.117.camel@maggy.simson.net> <20101116211431.GA15211@tango.0pointer.de> <201011182333.48281.hpj@urpla.net> <20101118231218.GX6024@const.famille.thibault.fr> <1290123351.18039.49.camel@maggy.simson.net> <20101118234339.GA6024@const.famille.thibault.fr> <1290167376.2109.1553.camel@laptop> <1290169178.2109.1573.camel@laptop> <20101119125548.GC24411@Krystal> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Fri, 19 Nov 2010 14:00:48 +0100 Message-ID: <1290171648.2109.1580.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 937 Lines: 25 On Fri, 2010-11-19 at 07:55 -0500, Mathieu Desnoyers wrote: > > > In general though, I think you can say that: cgroups ass overhead. > > I really think you meant "add" here ? (Hey! The keys were next to each other!) > ;) Uhm, quite! > > Simply because you add constraints, this means you need to 1) account > > more, 2) enforce constraints. Both have definite non-zero cost in both > > data and time. > > Yep, this looks like one of these perpetual throughput vs latency trade-offs. > Trade-off sure, throughput vs latency only in a specific use-case, its more a feature vs cost thing, just like all them trace people want lower cost tracing but want more features at the same time.. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/