From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58936) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WPBAo-0006Gz-Bl for qemu-devel@nongnu.org; Sun, 16 Mar 2014 09:32:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WPBAf-0001gJ-U0 for qemu-devel@nongnu.org; Sun, 16 Mar 2014 09:32:18 -0400 Received: from mail-pd0-x230.google.com ([2607:f8b0:400e:c02::230]:37890) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WPBAf-0001g1-MT for qemu-devel@nongnu.org; Sun, 16 Mar 2014 09:32:09 -0400 Received: by mail-pd0-f176.google.com with SMTP id r10so4489890pdi.35 for ; Sun, 16 Mar 2014 06:32:08 -0700 (PDT) Message-ID: <5325A7F0.9000300@gmail.com> Date: Sun, 16 Mar 2014 21:32:32 +0800 From: Chen Gang MIME-Version: 1.0 References: <1394205380-31875-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <1394205380-31875-5-git-send-email-aneesh.kumar@linux.vnet.ibm.com> <531B21F1.7030009@gmail.com> In-Reply-To: <531B21F1.7030009@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 4/5] hw/9pfs: use g_strdup_printf() instead of PATH_MAX limitation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Aneesh Kumar K.V" Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, anthony@codemonkey.ws On 03/08/2014 09:58 PM, Chen Gang wrote: > OK, thanks. > > Next, I will/should continue to analyse the performance issue for 9pfs > when users drop into a long directory path under bash shell. > After have a test, I am sure it is not 9pfs issue, either not Qemu's issue, it's Linux kernel vfs or block sub-systems' issue. The related test environments (originally, our 9pfs is upper on ext4): - for ext4 file system under my Fedora laptop (Qemu does not start). - for ntfs file system under my Fedora laptop (Qemu does not start). - for ext4 file system under my Ubuntu in Qemu. For a very long file name (e.g. > 3K long), all of them are very very slow. (and I also tested the ext2 /boot partition under Ubuntu in Qemu, it is not slow, I guess the reson is its partition size is small). Next, I will/shall communicate with upstream kernel for it. :-) > Although I am not quite sure, hope I can find the root cause within > month (2014-03-31). > > Welcome any suggestions, discussions, and completions for it. > > Thanks. > -- Chen Gang Open, share and attitude like air, water and life which God blessed