From owner-freebsd-fs@freebsd.org Wed Jul 29 21:13:51 2015 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 35CF99AEB61 for ; Wed, 29 Jul 2015 21:13:51 +0000 (UTC) (envelope-from javocado@gmail.com) Received: from mail-la0-x231.google.com (mail-la0-x231.google.com [IPv6:2a00:1450:4010:c03::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AFB70147D for ; Wed, 29 Jul 2015 21:13:50 +0000 (UTC) (envelope-from javocado@gmail.com) Received: by lagw2 with SMTP id w2so13890873lag.3 for ; Wed, 29 Jul 2015 14:13:48 -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=j4hO9STThkXuLOvWJ9WMAi2Cux6SicywGcdyJGTbebA=; b=M4lYuI4GZmJiTHbh8kmteHTKbzSmHNA9K7z/boKwr/CPqSvpV/gvu7IQVqtjfRsrPD 8d4S5sGk4FfML3aGkh/mDEPT1rMqb3oLaGMJpzXd1JJPNl6/jYyGWmSHewLD50rV0XyS cPo9N2o80VkgfaAf7qz/hPKg4M4sg9yQgz26e1vz4Ees3Crp186QOq1Ga5c6fyXtCaPQ G975zDiuTdM3jMv22Hs3vaUilk+HmtZf+8WJqDr7hK5+4mQOhzfVZioHzFP02b5cDoJp WapELGh2IN5FUiNr0tilngH2XobGI62Fj9Y7ACk7Vi8YaI7w6VltWQOtTAILwXGkvZYr obhQ== MIME-Version: 1.0 X-Received: by 10.112.219.70 with SMTP id pm6mr40044213lbc.41.1438204428768; Wed, 29 Jul 2015 14:13:48 -0700 (PDT) Received: by 10.114.96.8 with HTTP; Wed, 29 Jul 2015 14:13:48 -0700 (PDT) In-Reply-To: References: Date: Wed, 29 Jul 2015 14:13:48 -0700 Message-ID: Subject: Re: pw operations slow under zfs load From: javocado To: FreeBSD Filesystems Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Jul 2015 21:13:51 -0000 Sorry, the boot disk (SSD) is plain old ufs. On Wed, Jul 29, 2015 at 2:11 PM, javocado wrote: > Hi, > > We have a pretty busy ZFS pool running on an 8.3 AMD system. We are > noticing that when the pool is busy pw-related operations seem to take a > long time to complete: > > # time pw unlock 1000 > 0.007u 0.036s 0:39.72 0.0% 45+1953k 0+113io 0pf+0w > > # time pw lock 1000 > 0.032u 0.022s 1:09.63 0.0% 24+1132k 0+114io 0pf+0w > > Wile the command is running, we note that the process is locked in the D > state: > > root 85051 0.0 0.0 5832 960 0 D+ 1:53PM 0:00.02 > /usr/sbin/pwd_mkdb -u 1000 /etc/master.passwd > > We also note that there is next to 0 disk activity on the boot volume: > > # gstat -f ad > > dT: 1.005s w: 1.000s filter: ad > L(q) ops/s r/s kBps ms/r w/s kBps ms/w %busy Name > 0 0 0 0 0.0 0 0 0.0 0.0| ad6 > 0 0 0 0 0.0 0 0 0.0 0.0| ad8 > 0 0 0 0 0.0 0 0 0.0 0.0| ad10 > 0 0 0 0 0.0 0 0 0.0 0.0| ad12 > > And plenty of free mem: > > Mem: 400M Active, 3391M Inact, 128G Wired, 1935M Cache, 14G Buf, 6055M Free > > So, what's going on here? How does a busy pool with it's own set of drives > (which operate off an HBA) affect the speed of operations involving the > boot volume (an SSD connected to the mobo)? > >