2013-11-13 02:30:09

by Harry Edmon

[permalink] [raw]
Subject: Re: NFS over RDMA stops working for data larger than 812 Bytes

Klemens Senn <klemens.senn@...> writes:

>
> Hi,
>
> I started setting up NFS over RDMA on a OpenSUSE 12.3 machine using the
> 3.7.10-1.16-default kernel.
> Mounting the NFS share works and getting a file with 812 Bytes succeeds.
> Reading 813 Bytes raises a Input/output error.
>
> The export on the server side is done with
> /data
>
172.16.100.0/24(rw,wdelay,crossmnt,insecure,no_root_squash,no_subtree_check,
fsid=0,mountpoint)
>
> Following command is used for mounting the NFSv4 share:
> mount -t nfs -o port=20049,rdma,vers=4.0,timeo=900 172.16.100.2:/ /mnt/
>
> Testing the client side with older kernels stated that the mount is
> working properly with the 3.4.67 kernel. I continued testing with the
> 3.10.17 kernel and enabled the debug level and noticed the message
> "server cheating in read reply: count 813 > recvd 0"


I am seeing the same thing on an Debian 7.2 RDMA client running the 3.12
kernel.