From owner-freebsd-hackers@FreeBSD.ORG Thu Jul 25 01:04:18 2013 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 43ED8606; Thu, 25 Jul 2013 01:04:18 +0000 (UTC) (envelope-from superbisquit@gmail.com) Received: from mail-oa0-x22a.google.com (mail-oa0-x22a.google.com [IPv6:2607:f8b0:4003:c02::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id DB0102462; Thu, 25 Jul 2013 01:04:17 +0000 (UTC) Received: by mail-oa0-f42.google.com with SMTP id j6so2863393oag.29 for ; Wed, 24 Jul 2013 18:04:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=2uN7lFesbOCR5N86YX2eUGdhDur1ZJFzmHKl1OtS+Oo=; b=BPk7dwXCJZldRhJOlkubjjSAhcQomMCVDzJ3E2JqL+wIb48bx51wgRi1yh5oOKlnLI iOAvL0FTUDmwe7HXcBYklrkDLynC7thZgBnZX81bquWYH2vJjffDZ6dFgFyDeSGzBMuF Vgwwhxgyq0ozktgr8IDhZm9hjC53oIqQc+Qehyg1hoPTGwn6Az5ytV1185evjm6bRUQa sjveWACp2JuuAQyJSN123IHXc0fiWGBMqSXqWDMGEODM6UiMSGSFVBaj0dlao8yVhIvn MKpqJufDAsEnYhLGhFg3koXTiK5yxrOm0GxDslMYFd5qECVwC8+hY4IsFAEjjAuSdamx uleA== MIME-Version: 1.0 X-Received: by 10.60.125.100 with SMTP id mp4mr39510828oeb.60.1374714257003; Wed, 24 Jul 2013 18:04:17 -0700 (PDT) Received: by 10.182.115.194 with HTTP; Wed, 24 Jul 2013 18:04:16 -0700 (PDT) In-Reply-To: References: Date: Wed, 24 Jul 2013 21:04:16 -0400 Message-ID: Subject: Re: Kern.hz= +1 hertz at anything 2500 and above. From: Super Bisquit To: Adrian Chadd , FreeBSD PowerPC ML , freebsd-current , FreeBSD Hackers Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Jul 2013 01:04:18 -0000 When I started with FreeBSD on a G3 B&W, I noticed that the performance improved with a higher kern.hz rating. Unless the future holds an emu20k2, there will be RAM used from the motherboard. 1. I will need a real-time or a faster kernel- hence the high rate wanted- because the devices to be built will be used in an active environment: art, music, audio control. 2. Any system with limited memory and a low CPU hertz rate benefits from the higher kern.hz setting. 3. Why not? If it works for PowerPC, SPARC64, AMD64, and i386 then it may work for other architectures. 4. Some applications may be ran from within a jail. On Wed, Jul 24, 2013 at 8:16 PM, Adrian Chadd wrote: > Well, why is it reducing latency? That's the thing you should investigate. > > Is it because processes aren't getting enough time? or too much time? > Or the audio device isn't getting enough time to run? etc. > > > > -adrian > > On 24 July 2013 15:35, Super Bisquit wrote: > > > http://lists.freebsd.org/pipermail/freebsd-stable/2009-September/051789.html > > > > This is the thread that I was referring to earlier. Since the patch is > for > > 2009, what are the chances it would work with 10.x or 9.x? > > > > On PowerPC machines with a low MHz rate- or any machine with a CPU rate > of > > 800 MHz or less- increasing the kern.hz improves performance and cuts > down > > on latency. I am building audio applications and suites that are used in > > different projects. A G3 based machine should be able to run a kernel > with > > kern.hz=5000 with no problem. Unfortunately, this cannot be done. > > > > @PowerPC: some of you may find that performance does increase at a higher > > kern.hz rate. > > > > @Hackers & Current: What's the chance that the default rate limit can be > > raised to 5k? > > _______________________________________________ > > freebsd-ppc@freebsd.org mailing list > > http://lists.freebsd.org/mailman/listinfo/freebsd-ppc > > To unsubscribe, send any mail to "freebsd-ppc-unsubscribe@freebsd.org" >