NFS Trouble on copying large files (400Mb+)

Yalla-One · 03-17-2007, 04:38 AM

I'm having some performance trouble copying multiple large files over NFS from a laptop with a wireless interface (madwifi) to a server.

On the server, dmesg and /var/log/messages have no surprises, but on the client (the laptop) I get the following messages in /var/log/messages:

Code:

ar 17 10:32:38 asterix kernel: nfs: server majestix not responding, still tryin
g
Mar 17 10:32:49 asterix kernel: nfs: server majestix OK
Mar 17 10:32:49 asterix kernel: nfs: server majestix OK
Mar 17 10:32:52 asterix kernel: nfs: server majestix not responding, still tryin
g
Mar 17 10:32:52 asterix kernel: nfs: server majestix not responding, still tryin
g
Mar 17 10:32:52 asterix kernel: nfs: server majestix OK
Mar 17 10:32:55 asterix kernel: nfs: server majestix not responding, still tryin
g
Mar 17 10:32:56 asterix kernel: nfs: server majestix OK
Mar 17 10:32:56 asterix kernel: nfs: server majestix OK
Mar 17 10:33:07 asterix kernel: nfs: server majestix not responding, still tryin
g
Mar 17 10:33:07 asterix last message repeated 2 times
Mar 17 10:33:07 asterix kernel: nfs: server majestix OK
Mar 17 10:33:07 asterix last message repeated 3 times
Mar 17 10:33:12 asterix kernel: nfs: server majestix not responding, still tryin
g

As far as I can tell I do not suffer from lost or corrupted files, but clearly something is wrong..

The bitrate on the card is set to 54Mbit/s

Code:

iwlist bitrate
lo        no bit-rate information.

eth0      no bit-rate information.

wifi0     no bit-rate information.

ath0      12 available bit-rates :
          1 Mb/s
          2 Mb/s
          5.5 Mb/s
          6 Mb/s
          9 Mb/s
          11 Mb/s
          12 Mb/s
          18 Mb/s
          24 Mb/s
          36 Mb/s
          48 Mb/s
          54 Mb/s
          Current Bit Rate=54 Mb/s

Where else should I look, and what other information is relevant?

Thanks for any insight!

EDIT: Seems like the error is only present while on wireless - when shutting down ath0, the copy works just fine with no error messages. Hence I assume (correct me if I'm wrong) that the problem is madwifi, and not NFS related.. Hopefully the upcoming 0.9.3. might have a fix

erklaerbaer · 03-17-2007, 07:54 AM

wifi is a noisy medium. have you tried placing the laptop and your server abreast?
however if there is no data corruption (md5sum?), i would not worry too much about that.

( have you tried rsync? if you don't want to work over network with the files, but just copy them, it could be a better alternative. )

Yalla-One · 03-17-2007, 08:29 AM

Hello, and thanks for answering.

The laptop is 3-4 meters away from the accesspoint, but is the only one to have trouble compared to two other wireless laptops using the same network.

I use NFS for lots of traffic, everything from hosting my digital music collection to disk storage and backup.

While the very low performance and multiple errors on wireless transfer is not a show-stopper it's definitely a sign that something is wrong, and thus deserves my attention :-)

rsync is fine for bulk upgrades (ie for the nightly transfers of slackware-current (which have been quite slow for the past 6 months) and backups), but is not suitable for day to day use..

-Y1