From owner-freebsd-xen@FreeBSD.ORG Fri Jan 30 14:13:41 2009 Return-Path: Delivered-To: freebsd-xen@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0D581106566B for ; Fri, 30 Jan 2009 14:13:41 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: from fk-out-0910.google.com (fk-out-0910.google.com [209.85.128.186]) by mx1.freebsd.org (Postfix) with ESMTP id 89D478FC13 for ; Fri, 30 Jan 2009 14:13:40 +0000 (UTC) (envelope-from ivoras@gmail.com) Received: by fk-out-0910.google.com with SMTP id f40so503215fka.11 for ; Fri, 30 Jan 2009 06:13:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=LGSbsl7+4m4JaBBfMNGyJ68yLjC0S9tMieGVxvbb0B8=; b=UaIIrnF3mVBVRdftugMVT3e7CT2TabHt4D7haz1xiI6s3WsE4trUxJfg8rKGxh42Hc X3ULKYU9bfPlKAM4gAdG1dnjE0iOjGwTmCzz+m90J9DxU/Oo1h05VpQ4by2CvQhp0Uxh jeRMqlJP9jw2YHRr5ZqlZJ2Me6ZmxFmwXuvB0= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=A9K+bAedo4xaLRdb2a4PSP1n7YZNk6/1fw8hEPRmezhbjviJ+FrCQuUP4EAK+i01xM w8NJTUpu1dM/+gq1LTqM3foW7snoCf02Yt/WQoyXkId2NDvc42tQdF4O1fI2V02JoB7P WRzqsexotw8viv+V4s8kL1SQeirMXBf8UFpVU= MIME-Version: 1.0 Sender: ivoras@gmail.com Received: by 10.181.239.8 with SMTP id q8mr455130bkr.1.1233324818959; Fri, 30 Jan 2009 06:13:38 -0800 (PST) In-Reply-To: <1233319967.24925.19.camel@phoenix.blechhirn.net> References: <87ocxp1tym.fsf@tabernacle.localnet> <1233285247.24925.4.camel@phoenix.blechhirn.net> <871vul1nqk.fsf@tabernacle.localnet> <9bbcef730901300214s19c91071vf9241cd7cd40ba57@mail.gmail.com> <1233319967.24925.19.camel@phoenix.blechhirn.net> Date: Fri, 30 Jan 2009 15:13:38 +0100 X-Google-Sender-Auth: 536f782c5ca70a32 Message-ID: <9bbcef730901300613h1d4a3565xd6a0cbea4f70af00@mail.gmail.com> From: Ivan Voras To: mister.olli@googlemail.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: freebsd-xen@freebsd.org, Julian Stecklina Subject: Re: kern.hz = 10 X-BeenThere: freebsd-xen@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussion of the freebsd port to xen - implementation and usage List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Jan 2009 14:13:41 -0000 2009/1/30 Mister Olli : > I've run on 100HZ quite some time now and did have the impression that > 8-CURRENT is slow. It's even faster on copy processes as 7 under VMware > on a host machine which is 3 years younger... This might or (probably) might not be due to HZ. If you're interested in testing, here's what you should do: 1. compile a 8-CURRENT kernel without debugging (WITNESS, INVARIANTS & their support kernel options) 2. compile a 8-CURRENT world without malloc debugging (see http://wiki.freebsd.org/DefaultDebuggingKnobs) 3. run some repeatable tests - I'd suggest some file system benchmarks on a RAM (md) drive, see http://man.freebsd.org/md like bonnie++ and blogbench and some network tests with iperf 4. change HZ in loader.conf and test again, in exactly the same way as before (in 3.) Benchmarks that are not repeatable are useless. Repeatable means by you (so e.g. the host machine must be in the same state - no additional programs running, etc., see http://wiki.freebsd.org/BenchmarkAdvice) and by others when following your steps exactly.