From: "Jake Hammer" Subject: RE: NFS read ok, write ok, simultaneous R+W=TERRIBLE Date: Wed, 4 Dec 2002 21:55:14 -0800 Sender: nfs-admin@lists.sourceforge.net Message-ID: References: <3DEEDD90.915BAFF7@amis.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: "NFS" Return-path: Received: from cynaptic.com ([128.121.116.181]) by sc8-sf-list1.sourceforge.net with esmtp (Exim 3.31-VA-mm2 #1 (Debian)) id 18Joyx-0001oT-00 for ; Wed, 04 Dec 2002 21:55:31 -0800 To: "Eric Whiting" In-Reply-To: <3DEEDD90.915BAFF7@amis.com> Errors-To: nfs-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Unsubscribe: , List-Archive: Hi All, Eric, > 1. Make sure your network is clean and doing duplex right. (test using > two ftp sessions moving those 10 gig files -- one reading while one > writes) Ftp will let you know if the TCP part of your network is healthy > under full duplex loads. Network is pristine and duplex is 100% correct. Our Sun and NetApp gear works great. > 2. Try TCP mounts They are even slower with read+write! 1-2MB/sec! > 3. Try NFS V3 Not [well] supported for TCP. Since the Neil Brown patches enable it, I tried both UDP and TCP. Both are the same on read+write. UDP is faster by 10-15% on read/write but the same on read+write. > 4. Make sure your IDE RAID system on the server is healthy. Can it > handle concurrent read/write processes on the local box -- with NFS out > of the picture? Local read/write and read+write is *great* - no issues at all. Local write is ~100MB/sec, local read is ~120MB/sec, and local read+write is ~105MB/sec. It's not the disk subsystem. > What is the filesystem you have on the RAID5 setup? > reiserfs/ext3/xfs/jfs? > What sort of IDE HW raid supports 14 disks? Or are you using SW raid? 2 x 8 port 3ware IDE RAID cards, RAID 5 done in software by 2.4.19 IBM EVMS. Filesystem is EXT3, mounted with defaults. 14 disks. To summarize: Local disk is fast read, write, and read+write. NFS is sort of fast for read and for write, but it *utterly* dies on read + write UDP and TCP. Network is clean. > I would like to see a solution to this sort of problem as well. Glad you're seeing it as well. I hope it can be sorted out. Thanks, Jake ------------------------------------------------------- This SF.net email is sponsored by: Microsoft Visual Studio.NET comprehensive development tool, built to increase your productivity. Try a free online hosted session at: http://ads.sourceforge.net/cgi-bin/redirect.pl?micr0003en _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs