From owner-freebsd-hackers Sat Apr 27 23:26: 4 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from iguana.icir.org (iguana.icir.org [192.150.187.36]) by hub.freebsd.org (Postfix) with ESMTP id 5B11037B419 for ; Sat, 27 Apr 2002 23:26:01 -0700 (PDT) Received: (from rizzo@localhost) by iguana.icir.org (8.11.6/8.11.3) id g3S6Q0W63426; Sat, 27 Apr 2002 23:26:00 -0700 (PDT) (envelope-from rizzo) Date: Sat, 27 Apr 2002 23:26:00 -0700 From: Luigi Rizzo To: Marcelo Carvalho Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Clock granularity, dummynet & netperf Message-ID: <20020427232600.E63189@iguana.icir.org> References: <20020427224315.64485.qmail@web14402.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20020427224315.64485.qmail@web14402.mail.yahoo.com> User-Agent: Mutt/1.3.23i Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, Apr 27, 2002 at 03:43:15PM -0700, Marcelo Carvalho wrote: ... > According to my first results (even a simple ping > shows it), the delays are not properly set by > dummynet. Ok, the HZ option is set initially to 100. actually you should give a more detailed description of what goes wrong or it is impossible to comment what you are seeing. same for netperf. cheers luigi > Following Luigi's recommendations, I've increased HZ > to 1000. It turns out that I'm now getting > segmentation faults when I run netperf! > > I've tried to play around with the quantum clock as > well without success... I've increased it and the > measurements get really wild, totally inconsistent. > > I've read Luigi's previous message about the impact > on select() behavior on softwares that are not aware > of this. So, considering that so many people have > played around with the HZ option and could perform > measurements without no problem, is there a patch to > netperf that overcomes this problem or a better > software for performance evaluation as good (or > better) than netperf??? > > In case not, is anybody here familiar with this > problem and has fixed it in the past? I would really > appreciate any help, comments, etc. > > Thanks, > Marcelo. > > > > > > __________________________________________________ > Do You Yahoo!? > Yahoo! Health - your guide to health and wellness > http://health.yahoo.com > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hackers" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message