From mboxrd@z Thu Jan 1 00:00:00 1970 From: Neil Horman Subject: Re: NFS response time Date: Wed, 26 Jan 2005 07:46:54 -0500 Message-ID: <41F7913E.9030404@redhat.com> References: <003a01c50326$73182550$7889b38b@alpin> <41F6BD96.4040409@redhat.com> <004101c50329$3e016b30$7889b38b@alpin> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed 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 1CtmZh-0003lw-QQ for nfs@lists.sourceforge.net; Wed, 26 Jan 2005 04:47:09 -0800 Received: from mx1.redhat.com ([66.187.233.31]) by sc8-sf-mx2.sourceforge.net with esmtp (TLSv1:AES256-SHA:256) (Exim 4.41) id 1CtmZg-00033v-5a for nfs@lists.sourceforge.net; Wed, 26 Jan 2005 04:47:09 -0800 To: Duv Dek In-Reply-To: <004101c50329$3e016b30$7889b38b@alpin> 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: Duv Dek wrote: > Yes, it is program that we wrote. It is doing some mathematical > calculations, so it utilizes full CPU. Other linux programs are not > getting very slow when this program runs, but client computers sometimes > wait half a minute in order to reach a file on nfs server. Logging in to > the client computers take around 10 minutes. Normally it takes no more > than 20 seconds. I mean nfs is almost locking, but no other linux > program is badly affected. At least we should be able to give better > priority nfs via renice but we couldn't figure it out. Doing renice -20 > to all root programs didn't make nfs faster. > I assume that you included your program in the renice? If it still didn't help, my immediate thought would be to enable nfsd_debug, try to access the NFS share from a client, and check the message log. That would at least tell you if the NFS server is receiving the NFS transactions, and if so, where they might be taking the most time in processing. That may give you a clue as to where the delay is comming from, be it a scheduling delay from high CPU load, or contention on another resource that is in short supply on your system. Neil > > > ----- Original Message ----- From: "Neil Horman" > To: "Duv Dek" > Cc: > Sent: Tuesday, January 25, 2005 11:43 PM > Subject: Re: [NFS] NFS response time > > >> Duv Dek wrote: >> >>> Hi >>> We have a problem with our NFS server on Redhat 9. In case a program >>> on the server uses high CPU, the NFS clients almost lock and nfs >>> stops giving response until that program lowers its CPU usage. We >>> tried to increase the priority of nfsd deamons with renice, and also >>> tried to increase the number of nfsd threads, decreased the priority >>> of the program using high CPU with renice, but none of them worked. >>> How can we solve this problem so that nfs does not lock? >>> >> Have your tried to ascertain which process on your system is >> responsible (or most responsible) for the high CPU utilization? >> >> Neil >> >> -- >> /*************************************************** >> *Neil Horman >> *Software Engineer >> *Red Hat, Inc. >> *nhorman@redhat.com >> *gpg keyid: 1024D / 0x92A74FA1 >> *http://pgp.mit.edu >> ***************************************************/ >> > -- /*************************************************** *Neil Horman *Software Engineer *Red Hat, Inc. *nhorman@redhat.com *gpg keyid: 1024D / 0x92A74FA1 *http://pgp.mit.edu ***************************************************/ ------------------------------------------------------- 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