From: Brad Barnett Subject: Re: knfsd brought to its knees, by a simple rsync or cp operation Date: Mon, 28 Feb 2005 10:23:07 -0500 Message-ID: <20050228102307.3788a184@be.back.l8r.net> References: <20050226082854.2a496ec3@be.back.l8r.net> <20050228100633.GA4822@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: nfs@lists.sourceforge.net Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list2.sourceforge.net with esmtp (Exim 4.30) id 1D5mjn-00078p-Oa for nfs@lists.sourceforge.net; Mon, 28 Feb 2005 07:23:11 -0800 Received: from l8r.net ([64.26.155.43] ident=aliens) by sc8-sf-mx2.sourceforge.net with esmtp (TLSv1:DES-CBC3-SHA:168) (Exim 4.41) id 1D5mjl-0004nr-TH for nfs@lists.sourceforge.net; Mon, 28 Feb 2005 07:23:11 -0800 To: Olaf Kirch In-Reply-To: <20050228100633.GA4822@suse.de> Sender: nfs-admin@lists.sourceforge.net Errors-To: nfs-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Post: List-Help: List-Subscribe: , List-Archive: On Mon, 28 Feb 2005 11:06:33 +0100 Olaf Kirch wrote: > On Sat, Feb 26, 2005 at 08:28:54AM -0500, Brad Barnett wrote: > > There is obviously something wacky in the way the kernel is scheduling > > things here. Any ideas, patches, suggestions? > > That's because knfsd will write things to disk synchronously unless you > tell it not to. That can throttle other NFS activity in two locations: During my tests involving "ls", no one else was accessing the server. I have noatime set for both client and server mounts.. just in case. So, there should be no writes for knfsd to do. There was only one read operation, and that was a "ls -R /nfsmount". > > - by tying up all knfsd threads on the server. Try to bump the > number of nfsd processes > > - by tying up all RPC slots on the client. Make sure your wsize > isn't too big (8k is reasonable) There is only one client (during my tests), so #1 can't be the case. Number 2 applies to writes operations, although I have spent over 5 hours trying every possible permutation to see if any significant advantage can be had. This is what I don't understand. Why is one single 'ls' on a single client, the only nfs client, brought to a standstill by a single cp or rsync? It's very weird, and it does not seem to be because of write operations the client is performing. > > Olaf > -- > Olaf Kirch | --- o --- Nous sommes du soleil we love when we play > okir@suse.de | / | \ sol.dhoop.naytheet.ah kin.ir.samse.qurax > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > NFS maillist - NFS@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/nfs ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs