From mboxrd@z Thu Jan  1 00:00:00 1970
From: Kay Sievers <kay.sievers@vrfy.org>
Date: Sun, 03 May 2009 12:56:06 +0000
Subject: Re: very slow NFS boot on linux-next and -mm
Message-Id: <ac3eb2510905030556p4ce25ff1w9aa5cbf76be2e206@mail.gmail.com>
List-Id: <linux-hotplug.vger.kernel.org>
References: <20090503105456.GA30449@localhost> <20090503124013.GA31700@localhost>
In-Reply-To: <20090503124013.GA31700@localhost>
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: 8bit
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: linux-nfs@vger.kernel.org, Trond Myklebust <Trond.Myklebust@netapp.com>, linux-hotplug@vger.kernel.org

On Sun, May 3, 2009 at 14:40, Wu Fengguang <fengguang.wu@intel.com> wrote:

> The udevd is doing this busy loop like mad:
>
>        open("/etc/group", O_RDONLY|O_CLOEXEC)  = 7
>        lseek(7, 0, SEEK_CUR)                   = 0
>        fstat(7, {st_mode=S_IFREG|0644, st_sizey7, ...}) = 0
>        mmap(NULL, 797, PROT_READ, MAP_SHARED, 7, 0) = 0x7f6791601000
>        lseek(7, 797, SEEK_SET)                 = 797
>        munmap(0x7f6791601000, 797)             = 0
>        close(7)                                = 0
>
> udev version is 0.141-1.

Are you sure that's "busy loop" in that sense, and not just "load"?

If your config carries OWNER= or GROUP= rules in the udev rules, but
your system does not have these users or groups configured, glibc will
try to resolve these names to the uid/gid with every event that needs
these values.

If the in rules configured user/group names can be resolved at startup
of udevd, they will be cached and never looked up again.

Are you sure, that your system is configured correctly regarding the
used rules and referenced system users/groups names?

Thanks,
Kay