From owner-freebsd-fs@FreeBSD.ORG Tue Jan 8 16:42:51 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 2FE2C769 for ; Tue, 8 Jan 2013 16:42:51 +0000 (UTC) (envelope-from tjg@soe.ucsc.edu) Received: from mail-vb0-f50.google.com (mail-vb0-f50.google.com [209.85.212.50]) by mx1.freebsd.org (Postfix) with ESMTP id D4DD4C34 for ; Tue, 8 Jan 2013 16:42:50 +0000 (UTC) Received: by mail-vb0-f50.google.com with SMTP id ft2so597268vbb.9 for ; Tue, 08 Jan 2013 08:42:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ucsc.edu; s=ucsc-google; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=EEkZavG9v0O/6HER0TvtwSv9W7VeL//9OD6fU3C1Yns=; b=D005NwWibwzb6/tJFcZydHrWFa6lH5LbFnY31mJmo373j1v0fY+gqOs+bMKEQ5YK/y Mlegy9hXrNK65a4GLJaf7Fo+hgGJyC/Lw5cEuPbTx/bMIF/QrmhslzSTWMXhvxCJ5f/6 N4Ral7QWEceCOwBsLzMTCLRY4luG9Av63uzs8= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:x-gm-message-state; bh=EEkZavG9v0O/6HER0TvtwSv9W7VeL//9OD6fU3C1Yns=; b=O6vfqkwf8cJ8d9MXb1tTBSjTECievc/vdQHSuN+agj6d6XXgBZGGVMkrfGeVn2ncNA tvXQF1g53tvgx4kFSWV0aqgT7RAnrMQU4w/k15LnRY1eatS7f1GkyEafxnm7abJEf/5P jCYy9vUPYuU9x08EpXnolscqrkvQExQUsIziSO9NLMl2fHJ+Fzoj+jhRHOimRCVo9Hj6 1SIBf5BHseEQe1SIm0N6GqB+zMSCVmZvAvI7xokorZr6bLuX8o2Ylip9/qKkSvMBITky s9fp2GaGNdCqzKuwTz9r2plgDcDotL5RMcslEyW8HTNLFQPskrBDm3aDMuCm29iTAp2i OGqA== MIME-Version: 1.0 Received: by 10.52.97.7 with SMTP id dw7mr76364857vdb.38.1357663364201; Tue, 08 Jan 2013 08:42:44 -0800 (PST) Received: by 10.59.12.231 with HTTP; Tue, 8 Jan 2013 08:42:44 -0800 (PST) In-Reply-To: <20130108150508.GA2248@pm513-1.comsys.ntu-kpi.kiev.ua> References: <20130103123730.GA19137@pm513-1.comsys.ntu-kpi.kiev.ua> <20130108150508.GA2248@pm513-1.comsys.ntu-kpi.kiev.ua> Date: Tue, 8 Jan 2013 08:42:44 -0800 Message-ID: Subject: Re: Problems Re-Starting mountd From: Tim Gustafson To: Andrey Simonenko Content-Type: text/plain; charset=UTF-8 X-Gm-Message-State: ALoCoQmMChp59uh9U6aZF2mb+eNaI+jv68OCZgRtJQC+vgcDcjW1eRykzdiECVCN05aRQOWzKPOo Cc: FreeBSD Filesystems X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Jan 2013 16:42:51 -0000 > As I understood each /export/home/* pathname from /etc/exports is > a mount point for ZFS file system. Correct. > I created 2000 file systems on ZFS file system backed by vnode md(4) > device. The /etc/exports file contains 4000 entries like your example. > > On 9.1-STABLE mountd spends ~70 seconds in flushing current NFS exports > in the NFS server, parsing data from /etc/exports and loading parsed > data into the NFS server. ~70 seconds is not several minutes. Most of > time mountd spends in nmount() system call in "zio->io_cv" lock. I suspect that statfs(), nmount() and lstat() will return much more quickly for md-based file systems, since they have zero latency. > Can you show the output of "truss -fc -o /tmp/output.txt mountd" > (wait wchan "select" state of mountd and terminate it by a signal). > If everything is correct you should see N statfs() calls, N+M nmount() > calls and something*N lstat() calls, where N is the number of /etc/exports > lines, M is the number of mounted file systems. Number of lstat() calls > depends on number of components in pathnames. I will try to run this tonight; I can't do it now as people are already starting to work today. -- Tim Gustafson tjg@soe.ucsc.edu 831-459-5354 Baskin Engineering, Room 313A