Messages in this thread |  | | | Date | Fri, 5 Sep 2008 15:14:35 -0700 | | From | Aaron Straus <> | | Subject | Re: [NFS] blocks of zeros (NULLs) in NFS files in kernels >= 2.6.20 |
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Hi,
On Sep 05 04:36 PM, Chuck Lever wrote: > I have the latest Fedora 9 kernels on two clients, mounting via NFSv3 > using "actimeo=600" (for other reasons). The server is OpenSolaris > 2008.5. > > reader.py reported zeroes in the test file after about 5 minutes.
Awesome. Thanks for testing! Our actime is much shorter which is probably why it happens sooner for us.
> Looking at the file a little later, I don't see any problems with it. > > Since your scripts are not using any kind of serialization (ie file > locking) between the clients, I wonder if non-determinant behavior is > to be expected.
Hmm... yep. I don't know what guarantees we want to make. The behavior doesn't seem to be consistent with older kernels though... so I'm thinking it might be a bug.
We hit this particular issue because we have scripts which essentially 'tail -f' log files looking for errors. They miss log messages (and see corrupted ones) b/c of the NULLs. That's also why there is no serialization.... we don't need it when grep'ing through log messages. I'm bisecting now. I see a block of intricate-looking NFS patches, I'll try to narrow it down to a particular commit.
I'll also get the wireshark data at that point.
Thanks, =a=
-- =================== Aaron Straus aaron@merfinllc.com[unhandled content-type:application/pgp-signature] |  |