Kernel Bug Tracker – Bug 3608
Files get corrupt when reading from a network fs (nfs and smbfs) except they're already cached locally
Last modified: 2008-03-04 01:07:54 UTC
gentoo with vanilla kernel 2.6.9
x86: dual xeon 3.06ghz
If I read large files (~180mB) from a network fs (nfs _and_ smb) which are not
yet cached, I get corrupt files (checked with md5sum, cmp and diff). But if I
read the file again just after the first reading (while it's still in the local
mem-cache) I get the files without any corruption.
If I read the files from a local fs everything is fine.
Steps to reproduce:
Let's say /nfs is a directory the a nfs-server and /nfs/file has a size of 180mB.
Further let's say /local is a local directory and /local/sum.md5 contains the
_correct_ md5-sum of /nfs/file (built this directly on the server and
transferred it on an other way, so this file _is_ correct).
Now I do the following:
cp /nfs/file . # I see much transfer on eth0 while the file gets transferred
md5sum -c sum.md5 # Result: FAILED
cp /nfs/file . # There's almost no load on eth0 as the file is still in the
md5sum -c sum.md5 # Result: OK
so it seems there's something wrong with the local file-buffer or something like
Ok, I held this report short, but I'll attach a mail I sent on LKML which
contains much more details about what I checked...
Created attachment 3871 [details]
Here's a mail about this bug I sent on the LKML containing much more details
It's weird: I'm using 2 proc's (P4) with HT activated and if I deactivate HT I'm
experiencing much less problem (less files get corrupted in average) and if I
deactivate the whole smp-support (so I use only one proc without HT) everything
works fine, all problems gone!
So this seems to be rather a smp-related thing than fs-related...
I could NOT reproduce problem on 2.6.9 [SMP] (RHEL 4 AS) on x86_64 (Opteron 880,
both client and server) using files of 168M and 1.6G.
Does anyone still have this problem with recent kernels? It's been a while, must have been fixed..
Closing the bug. Please reopen if confirmed with latest kernel.