From owner-freebsd-stable@FreeBSD.ORG Fri Jan 8 16:31:57 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 36E711065693 for ; Fri, 8 Jan 2010 16:31:57 +0000 (UTC) (envelope-from garrettmoore@gmail.com) Received: from mail-iw0-f198.google.com (mail-iw0-f198.google.com [209.85.223.198]) by mx1.freebsd.org (Postfix) with ESMTP id DEA1F8FC18 for ; Fri, 8 Jan 2010 16:31:56 +0000 (UTC) Received: by iwn36 with SMTP id 36so13209754iwn.3 for ; Fri, 08 Jan 2010 08:31:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=kFFCRaToBqRiydJuKju8YsZloo86sVNUh+yMbaAq+Fk=; b=RFL7yBn+ljL2GamgxqMTjy3yWHt3UOpta2sg0w8wOa+s9GBRbEPcedL3LA95DlOSk0 3ihP4/kvu37ZYO1e0UJ7Iz3uq9DQt1nwoL/KgDLI/y1X79/KDuZPYYfaQVP53U0Cn4OW 5A/WQXLGbYM9jV106vJmmpsuKhU+jjaAPBd5E= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=df5dxhJJApdwmSjv/d5U4+L4O9K2vx1Q4Y9WVNy7S1tXGhmu/s3O3K1qvFtg4vNm7V v3Fv1T/QTB5DLMTPNhYMrYTpQSI025DLknMH3dsGSO9HeTsjR445Gafmr1qK+CelGy4w 66jHV16j9wb+1xA9tTLYGajY1zPLGObpRFBkI= MIME-Version: 1.0 Received: by 10.231.29.149 with SMTP id q21mr277420ibc.35.1262968311767; Fri, 08 Jan 2010 08:31:51 -0800 (PST) In-Reply-To: References: <7346c5c61001030842r7dc76199y51e4c1c90a3eea6e@mail.gmail.com> Date: Fri, 8 Jan 2010 11:31:51 -0500 Message-ID: <7346c5c61001080831w375d158fu5b1996ee58cb0f8d@mail.gmail.com> From: Garrett Moore To: freebsd-stable@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Re: ZFS performance degradation over time X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 08 Jan 2010 16:31:57 -0000 No, I haven't isolated the cause to only be uptime related. In my original email I mentioned that "as suggested by someone in the thread, it's probably not directly related to system uptime, but instead related to usage - the more usage, the worse the performance." I've been starting my system with different combinations of applications running to see what access patterns cause the most slowdown. So far, I don't have enough data to give anything concrete. This weekend I'll try some tests such as the one you describe, and see what happens. I have a strong suspicion that rTorrent is to blame, since I haven't seen major slowdowns in the last few days with rTorrent not running. rTorrent preallocates the space needed for the file download (and I'm downloading large 4GB+ files using it), and then writes to them in an unpredictable pattern, so maybe ZFS doesn't like being touched this way? On Wed, Jan 6, 2010 at 2:21 PM, Ivan Voras wrote: > On 3.1.2010 17:42, Garrett Moore wrote: > > > I'm having problems with ZFS performance. When my system comes up, > > read/write speeds are excellent (testing with dd if=/dev/zero > > of=/tank/bigfile and dd if=/tank/bigfile of=/dev/null); I get at least > > 100MB/s on both reads and writes, and I'm happy with that. > > > > The longer the system is up, the worse my performance gets. Currently my > > system has been up for 4 days, and read/write performance is down to > about > > 10MB/s at best. > > Are you sure you have isolated the cause to be only the uptime of the > machine? Is there no other change between the runs? E.g. did you stop > all other services and applications on the machine before doing the test > for the second time? Can you create a big file (2x memory size) when the > machine boots, measure the time to read it, then read it again after a > few days when you notice performance problems? > > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org" >