nfs and 2.4 / 2.6 compatibility

Hello,

I've a server running a Debian Linux with kernel 2.4.27
Since some days ago, i used a Suse 9.1 Linux desktop pc that mounts a nfs
shared directory from server, and was working fine. The kernel of this
desktop PC was 2.6.5

I've upgraded the desktop PC with a Suse 9.3 linux, based on a kernel 2.6.11
and after this upgrade all nfs operations are very slow.

For example, my 2.4.27 server share the directory /home/myshare.

On desktop PC, the /home/myshare is mounted on /mnt/myshare.

With the previous version of kernel, read and write operations on this mount
point was very fast.

After the kernel upgrade, write operation are very slow, data read seems
slower than previous kernel, and often i have several files like:

..nfs002115f300000008

on the directories.
Here is an example:
# ls -la
-rw-r--r-- 1 dve dve 1100 2005-11-15 10:02 Makefile
-rwxr-xr-x 1 dve dve 81292 2005-11-14 18:28 .nfs002115f300000008*
-rwxr-xr-x 1 dve dve 102399 2005-11-15 18:44 .nfs0022a8e900000002*
-rwxr-xr-x 1 dve dve 81292 2005-11-14 18:32 .nfs0022a8ea00000009*
-rwxr-xr-x 1 dve dve 64614 2005-11-09 16:30 .nfs002545d000000002*
-rwxr-xr-x 1 dve dve 64790 2005-11-09 16:34 .nfs0025fe2a00000003*
-rwxr-xr-x 1 dve dve 81284 2005-11-14 16:54 .nfs002614dc00000007*
-rwxr-xr-x 1 dve dve 108063 2005-11-23 13:53 .nfs002614e400000001*
-rwxr-xr-x 1 dve dve 108287 2005-11-23 15:05 .nfs0026190d00000002*
-rwxr-xr-x 1 dve dve 108363 2005-11-23 15:53 .nfs0026191600000005*
-rwxr-xr-x 1 dve dve 108287 2005-11-23 15:09 .nfs0026191900000003*
-rwxr-xr-x 1 dve dve 108363 2005-11-23 15:55 .nfs0026191b00000006*
-rwxr-xr-x 1 dve dve 108319 2005-11-23 15:24 .nfs00261ef700000004*
-rwxr-xr-x 1 dve dve 108767 2005-11-28 16:18 .nfs0026202d00000002*


All other files seems good, and no messages appears on client/server log.
Another thing: when writing a big file i notice that the CPU usage is very
low, but the writing program take a long time to write the file. (For
example a simple cp of a local file to a remote directory).

Does anybody have an idea on what kind of problem may be that ?


Thank you

Gabriele


Gabriele Brugnoni

Gabriele Brugnoni wrote:
> Hello,
>
> I've a server running a Debian Linux with kernel 2.4.27
> Since some days ago, i used a Suse 9.1 Linux desktop pc that mounts a nfs
> shared directory from server, and was working fine. The kernel of this
> desktop PC was 2.6.5
>
> I've upgraded the desktop PC with a Suse 9.3 linux, based on a kernel 2.6.11
> and after this upgrade all nfs operations are very slow.
>
> For example, my 2.4.27 server share the directory /home/myshare.
>
> On desktop PC, the /home/myshare is mounted on /mnt/myshare.
>
> With the previous version of kernel, read and write operations on this mount
> point was very fast.
>
> After the kernel upgrade, write operation are very slow, data read seems
> slower than previous kernel, and often i have several files like:
>
> .nfs002115f300000008
>
> on the directories.
> Here is an example:
> # ls -la
> -rw-r--r-- 1 dve dve 1100 2005-11-15 10:02 Makefile
> -rwxr-xr-x 1 dve dve 81292 2005-11-14 18:28 .nfs002115f300000008*
> -rwxr-xr-x 1 dve dve 102399 2005-11-15 18:44 .nfs0022a8e900000002*
> -rwxr-xr-x 1 dve dve 81292 2005-11-14 18:32 .nfs0022a8ea00000009*
> -rwxr-xr-x 1 dve dve 64614 2005-11-09 16:30 .nfs002545d000000002*
> -rwxr-xr-x 1 dve dve 64790 2005-11-09 16:34 .nfs0025fe2a00000003*
> -rwxr-xr-x 1 dve dve 81284 2005-11-14 16:54 .nfs002614dc00000007*
> -rwxr-xr-x 1 dve dve 108063 2005-11-23 13:53 .nfs002614e400000001*
> -rwxr-xr-x 1 dve dve 108287 2005-11-23 15:05 .nfs0026190d00000002*
> -rwxr-xr-x 1 dve dve 108363 2005-11-23 15:53 .nfs0026191600000005*
> -rwxr-xr-x 1 dve dve 108287 2005-11-23 15:09 .nfs0026191900000003*
> -rwxr-xr-x 1 dve dve 108363 2005-11-23 15:55 .nfs0026191b00000006*
> -rwxr-xr-x 1 dve dve 108319 2005-11-23 15:24 .nfs00261ef700000004*
> -rwxr-xr-x 1 dve dve 108767 2005-11-28 16:18 .nfs0026202d00000002*
>
>
> All other files seems good, and no messages appears on client/server log.
> Another thing: when writing a big file i notice that the CPU usage is very
> low, but the writing program take a long time to write the file. (For
> example a simple cp of a local file to a remote directory).
>
> Does anybody have an idea on what kind of problem may be that ?
>
>
> Thank you
>
> Gabriele

this might be a nfs version change (1 to 2) between SuSE 9.1 and 9.3. I
do not think it is a kernel matter.

Check wich server version you are running and configure the client
version as needed within the mount options (nfsvers=x).

greetz,
Eric

EricT wrote:
>
> this might be a nfs version change (1 to 2) between SuSE 9.1 and 9.3. I
> do not think it is a kernel matter.
>
> Check wich server version you are running and configure the client
> version as needed within the mount options (nfsvers=x).
>
> greetz,
> Eric


Thank you Eric,

After having checked the nfs versions supported in 2.4.27 (patched to
supports the window size of 32K),
i've tried the followings options in fstab:

rw,rsize=32768,wsize=32768,nfsvers=3


Things seems to works fine now (i hope).

Regards,
Gabriele