Re: NFS v3 cached directory content out of sync

[Stefan Egli <stefan.egli@gmail.com>]

Hi Trond,

> It sounds like a bug. You don't mention which client you are using.

from uname:
Linux (Ubuntu) 2.6.24-24-generic #1 SMP Tue Jun 30 19:54:36 UTC 2009
x86_64 GNU/Linux

from mount:
type nfs (ro,tcp,rsize=3D8192,wsize=3D8192,nfsvers=3D3,addr=3D192.168.X=
X.YY)

> You can tune the amount of time the client caches information by usin=
g
> the 'ac*' mount options. In this case, you will want to adjust the
> values of 'acdirmin' and 'acdirmax', probably setting them to zero.
>
> 'man 5 nfs' should provide you with more information.

Ok, so setting acdirmin=3D0 and acdirmax=3D0 would mean no directory
content caching, right?

>> =A0Question 4: If we'd somehow manually detected such a directory
>> content inconsistency - would there be something like a 'hey NFS
>> client, flush all NFS caches NOW' thing?
>
> No.

unmount / mount would - but that's obviously not feasible. bugger
there's nothing for that...

>> =A0Question 5: any of this related to commit 37d9d76d8b3a2ac5817e1fa=
3263cfe
>> 0fdb439e51: NFS: flush cached directory information slightly more re=
adily. ?
>
> You client should be seeing mtime changes when you are creating new
> files, so it shouldn't need to look at the ctime.
>
> The only time when ctime changes are relevant are if you use 'rsync' =
to
> copy the files without specifying --omit-dir-times.
> IOW: if something is explicitly setting the mtime on the directory.

Would have to check if that applies in our case. We're doing
backup/restore from tivoli (tsm) - maybe that guy is to be blamed
for not correctly updating mtime/ctimes ?

Cheers,
Stefan