From owner-freebsd-questions@FreeBSD.ORG Tue Nov 4 15:02:10 2008 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2820310656B1 for ; Tue, 4 Nov 2008 15:02:10 +0000 (UTC) (envelope-from dudu.meyer@gmail.com) Received: from wf-out-1314.google.com (wf-out-1314.google.com [209.85.200.171]) by mx1.freebsd.org (Postfix) with ESMTP id EBDD98FC35 for ; Tue, 4 Nov 2008 15:02:09 +0000 (UTC) (envelope-from dudu.meyer@gmail.com) Received: by wf-out-1314.google.com with SMTP id 24so3210687wfg.7 for ; Tue, 04 Nov 2008 07:02:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type :content-transfer-encoding:content-disposition:references; bh=f3fFVcGJJFwRCv1NPKqPWN7O7l68iYQn4d4ubbLgF/g=; b=ov7oVJ0F1jz/epajeQWrbc/tYLiTTE5jrq02TpsYSKM1QSDdeDqIvtaXbqGVg/P8Ka XQBEbodSL7XxskjTn8RXu0N6mm80uqA58t3eLUnalAz9/W+fXKKrnDGkdzunHrNhkPbN YBgaIkMTeuGvno3qysSCT/XiCVghgRI4qZvB0= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=DfX3hPV71ohuJgib4y9AnA3Dv7q8S+yLWR0a1fdvgdJxNSIMcaaCNqYihVoh9zlvc0 zNrtQ0FldbDepIfwiD1m4gTVpumEbGfASwZy3/mmZ1hLmJiqO2zQaV4YtZ1O2uYH1m6m i/YIkuGtv9pqxhYi1+JYOfUPD3Y/rNHO0L8dU= Received: by 10.142.81.7 with SMTP id e7mr814661wfb.320.1225810929243; Tue, 04 Nov 2008 07:02:09 -0800 (PST) Received: by 10.142.158.11 with HTTP; Tue, 4 Nov 2008 07:02:09 -0800 (PST) Message-ID: Date: Tue, 4 Nov 2008 13:02:09 -0200 From: "Eduardo Meyer" To: "Bill Moran" In-Reply-To: <20081104095508.f231a7e2.wmoran@potentialtech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20081104091801.ff0297b0.wmoran@potentialtech.com> <20081104095508.f231a7e2.wmoran@potentialtech.com> Cc: questions@freebsd.org Subject: Re: Disk top usage PIDs X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Nov 2008 15:02:10 -0000 On Tue, Nov 4, 2008 at 12:55 PM, Bill Moran wrote: > In response to "Eduardo Meyer" : > >> On Tue, Nov 4, 2008 at 12:27 PM, Eduardo Meyer wrote: >> > On Tue, Nov 4, 2008 at 12:18 PM, Bill Moran wrote: >> >> In response to "Eduardo Meyer" : >> >>> >> >>> I have some serious issue. Sometimes something happens and my disk >> >>> usage performance find its limit quickly. I follow with gstat and >> >>> iostat -xw1, and everything usually happens just fine, with %b around >> >>> 20 and 0 to 1 pending i/o request. Suddely I get 30, 40 pending >> >>> requests and %b is always on 100% (or more than this). >> >>> >> >>> fstat and lsof gives me no hint, because the type of programs as well >> >>> as the amount of 'em is just the same. >> >>> >> >>> How can I find the PID which is hammering my disk? Is there an "iotop" >> >>> or "disktop" tool or something alike? >> >> >> >> top -m io -o total >> > >> > Great, thats exactly what I was looking for, thank you a lot Mr Moran. >> >> I see syncer (40%) and bufaemon (10%) and after that, imapd. The first >> ones are kernel PIDs (36 and 37). >> >> PID USERNAME VCSW IVCSW READ WRITE FAULT TOTAL PERCENT COMMAND >> 36 root 2 2 0 31 0 31 40.79% bufdaemon >> 37 root 2 2 0 16 0 16 21.05% syncer >> 71501 vmail 4 0 0 0 0 0 12.00% imapd >> >> I guess it a symptom of some hardware problems, kernel itself is not >> supposed to do this many I/O, right? >> >> Sometimes PID 39, softdepflush, is always on top 3. > > Off the top of my head, it looks like you're exceeding what the hardware > can do. What kind of disks do you have in that system? It may be time > to get faster disks or expand to a high-performance RAID setup. Its a: Master: ad4 Serial ATA II I still think its a hw (disk or controller) problem. I have raised the following: kern.filedelay=90 kern.dirdelay=90 kern.metadelay=90 Now, my disk usage is back to 30% > > -- > Bill Moran > http://www.potentialtech.com > -- =========== Eduardo Meyer pessoal: dudu.meyer@gmail.com profissional: ddm.farmaciap@saude.gov.br