From owner-freebsd-hackers@FreeBSD.ORG Wed Apr 11 22:20:17 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 5DA96106566C for ; Wed, 11 Apr 2012 22:20:17 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id 256D88FC19 for ; Wed, 11 Apr 2012 22:20:17 +0000 (UTC) Received: by pbcwz17 with SMTP id wz17so1906053pbc.13 for ; Wed, 11 Apr 2012 15:20:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=Uc3cfRerxHMWKxtaiVXpGOaLV9Zxl3So4WGzXIvJMgI=; b=k9nfcti4Cy4LM0xyPTrC8PTH/nBfQtLbRj+BCfQhMa0X1mnZwpfVehMcyfuMzlKYVU jcxujPn2bO09X+x/LXiJk+SNwZq8ntESKVV8udK3PAwQ18CnmoYfyMWs2wT1UJSesdSb 32RIS+JneCGqWJtlNMm0X5jfdWORBGxMj3taclTxVJcMxNVR9O5SbyzK238cB2mIcFm1 mdNdXKO1RlIVP2RjxuvrMZ3xmKaW7yfftG5Y1Vs2042ijARc5SUIe6qrGXAlDaQvUo79 Sq8hL04ENl3NHaGXqZSIUI/XiQwIkqOrLs0goOiQohAAV3GO/b20KMDMerUm7vDOm2VV fSbw== MIME-Version: 1.0 Received: by 10.68.204.234 with SMTP id lb10mr1073302pbc.161.1334182811333; Wed, 11 Apr 2012 15:20:11 -0700 (PDT) Sender: adrian.chadd@gmail.com Received: by 10.143.9.11 with HTTP; Wed, 11 Apr 2012 15:20:11 -0700 (PDT) In-Reply-To: <20120410171926.67ece307@bhuda.mired.org> References: <4F2F7B7F.40508@FreeBSD.org> <4F366E8F.9060207@FreeBSD.org> <4F367965.6000602@FreeBSD.org> <4F396B24.5090602@FreeBSD.org> <4F3978BC.6090608@FreeBSD.org> <4F3990EA.1080002@FreeBSD.org> <4F3C0BB9.6050101@FreeBSD.org> <4F3E807A.60103@FreeBSD.org> <4F3E8858.4000001@FreeBSD.org> <4F7DE863.6080607@FreeBSD.org> <4F833F3D.7070106@FreeBSD.org> <20120410160513.0b322f68@bhuda.mired.org> <20120410171926.67ece307@bhuda.mired.org> Date: Wed, 11 Apr 2012 15:20:11 -0700 X-Google-Sender-Auth: BZXyA5p6TynHXswfqsPydNdNbro Message-ID: From: Adrian Chadd To: Mike Meyer Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-hackers@freebsd.org, Arnaud Lacombe Subject: Re: [RFT][patch] Scheduling for HTT and not only X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Apr 2012 22:20:17 -0000 The problem, IMHO, is none of this is in any way: * documented; * modellable by a user; * explorable by a user (eg by an easy version of schedgraph to explore things in a useful way. Arnaud raises a valid point - he's given a synthetic benchmark whose numbers are unpredictable. He's asking why. There are plenty of "complex systems interact complexly!" style answers, none of which are in any way useful to an end-user. Arnaud, have you ever used ktr/sched_graph to look at what's going on? I think it'd be a worthwhile step to begin documenting what's going on here. I'd also suggest (in a completely non-inflammatory way, so you may not be the right person to write it :-) perhaps keeping some kind of blog listing the tests you're doing and what the results of system inspection are. I think that kind of thing would be very very helpful for engineers and users who are looking to get better behaviour in their use case. This kind of thing is sorely lacking at the moment. Adrian