Hello Spencer, Monday, June 19, 2006, 5:47:21 PM, you wrote:
>> Hello Spencer, >> >> Thursday, June 15, 2006, 11:48:57 PM, you wrote: >> >> SS> On Thu, Robert Milkowski wrote: >> >> Hello nfs-discuss, >> >> >> >> Sometimes on nfs servers I get below messages and then I have >> >> performance problems. What are they about and what can I do about >> >> this? >> >> >> >> XXXX rpcmod: [ID 851375 kern.warning] WARNING: svc_cots_kdup no slots >> >> free >> >> XXXX last message repeated 700353 times >> >> SS> This is an error from the NFS server when it attempts to place >> SS> a request into the duplicate request cache and finds that >> SS> all of the ones in the duplicate request table are "in progress". >> >> SS> The maximum for the duplicate request cache is 1024. >> >> SS> The most effective way to increase the value is /etc/system >> SS> and the variable would be: rpcmod:cotsmaxdupreqs >> >> I set it to 8192 and see some problems with nfsd+zfs - like almost all >> threads hanging in ZFS and no actual IOs are happening while I can >> issue IOs to the same zfs filesystems locally (see nfsd threads hang >> in ZFS on zfs-discuss list). >> >> I did set rpcmod:cotsmaxdupreqs=8192 >> rpcmod:maxdupreqs=8192 >> >> Maybe it's too high? SS> Are you still receiving the original error message your reported SS> after making these changes? (the "no slots free" error) No more errors - thanks for hint. SS> If not, then the problem is in the local filesystem. SS> What you have done is just allowed the NFS server to use the SS> threads that it can create and not reject with error the incoming SS> requests. ok, thank you. -- Best regards, Robert mailto:rmilkowski at task.gda.pl http://milek.blogspot.com