* Turning off delegations in NFSv4 server?
@ 2008-01-10 19:57 Jeff Garzik
2008-01-10 20:00 ` J. Bruce Fields
0 siblings, 1 reply; 6+ messages in thread
From: Jeff Garzik @ 2008-01-10 19:57 UTC (permalink / raw)
To: NFS list, nfsv4
Besides hacking the code, is there an easy way to turn off NFSv4
delegations in the kernel v4 server?
I'd like to observe behavior of the Linux v4 client when delegations are
not available.
Thanks,
Jeff
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Turning off delegations in NFSv4 server?
2008-01-10 19:57 Turning off delegations in NFSv4 server? Jeff Garzik
@ 2008-01-10 20:00 ` J. Bruce Fields
2010-03-04 9:23 ` Matt Bernstein
0 siblings, 1 reply; 6+ messages in thread
From: J. Bruce Fields @ 2008-01-10 20:00 UTC (permalink / raw)
To: Jeff Garzik; +Cc: NFS list, nfsv4
On Thu, Jan 10, 2008 at 02:57:01PM -0500, Jeff Garzik wrote:
> Besides hacking the code, is there an easy way to turn off NFSv4
> delegations in the kernel v4 server?
>
> I'd like to observe behavior of the Linux v4 client when delegations are
> not available.
The easiest thing is probably just to turn off leases:
echo 0 >/proc/sys/fs/leases-enable
--b.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Turning off delegations in NFSv4 server?
2008-01-10 20:00 ` J. Bruce Fields
@ 2010-03-04 9:23 ` Matt Bernstein
2010-03-04 14:33 ` J. Bruce Fields
0 siblings, 1 reply; 6+ messages in thread
From: Matt Bernstein @ 2010-03-04 9:23 UTC (permalink / raw)
To: J. Bruce Fields; +Cc: NFS list, nfsv4
On Jan 10 2008 J. Bruce Fields wrote:
> On Thu, Jan 10, 2008 at 02:57:01PM -0500, Jeff Garzik wrote:
>> Besides hacking the code, is there an easy way to turn off NFSv4
>> delegations in the kernel v4 server?
>>
>> I'd like to observe behavior of the Linux v4 client when delegations are
>> not available.
>
> The easiest thing is probably just to turn off leases:
> echo 0 >/proc/sys/fs/leases-enable
I found this from two years ago, and am wondering
- is this still the easiest thing to do?
- is this on server, client or both?
- will it break anything else?
We have a CentOS 5.4 NFS3/NFS4/samba server with about 300 clients on its
subnet, and another 100-200 on another subnet, which under high load has
started kernel-panicking (sometimes in nfsd4_cb_recall).
I want to disable delegations to see if that cures our symptoms--but I
worry that turning leases off might cause other problems.
For now I'll probably do it anyway, given that status quo isn't stable :(
Matt
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^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Turning off delegations in NFSv4 server?
2010-03-04 9:23 ` Matt Bernstein
@ 2010-03-04 14:33 ` J. Bruce Fields
2010-03-05 15:12 ` Matt Bernstein
0 siblings, 1 reply; 6+ messages in thread
From: J. Bruce Fields @ 2010-03-04 14:33 UTC (permalink / raw)
To: Matt Bernstein; +Cc: NFS list, nfsv4
On Thu, Mar 04, 2010 at 09:23:26AM +0000, Matt Bernstein wrote:
> On Jan 10 2008 J. Bruce Fields wrote:
>> On Thu, Jan 10, 2008 at 02:57:01PM -0500, Jeff Garzik wrote:
>>> Besides hacking the code, is there an easy way to turn off NFSv4
>>> delegations in the kernel v4 server?
>>>
>>> I'd like to observe behavior of the Linux v4 client when delegations are
>>> not available.
>>
>> The easiest thing is probably just to turn off leases:
>> echo 0 >/proc/sys/fs/leases-enable
>
> I found this from two years ago, and am wondering
> - is this still the easiest thing to do?
> - is this on server, client or both?
> - will it break anything else?
>
> We have a CentOS 5.4 NFS3/NFS4/samba server with about 300 clients on its
> subnet, and another 100-200 on another subnet, which under high load has
> started kernel-panicking (sometimes in nfsd4_cb_recall).
Have you filed a bug with the backtraces?
> I want to disable delegations to see if that cures our symptoms--but I
> worry that turning leases off might cause other problems.
No, it shouldn't cause problems, at least for NFSv4 clients. (Samba may
be more reliant on leases, especially if Samba and NFSv4 clients are
acting on the same files at the same time--but I don't know.)
--b.
>
> For now I'll probably do it anyway, given that status quo isn't stable :(
>
> Matt
_______________________________________________
NFSv4 mailing list
NFSv4@linux-nfs.org
http://linux-nfs.org/cgi-bin/mailman/listinfo/nfsv4
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Turning off delegations in NFSv4 server?
2010-03-04 14:33 ` J. Bruce Fields
@ 2010-03-05 15:12 ` Matt Bernstein
2010-03-05 15:30 ` J. Bruce Fields
0 siblings, 1 reply; 6+ messages in thread
From: Matt Bernstein @ 2010-03-05 15:12 UTC (permalink / raw)
To: J. Bruce Fields; +Cc: Jeff Garzik, NFS list, nfsv4, Matt Bernstein
On Mar 4 J. Bruce Fields wrote:
> On Thu, Mar 04, 2010 at 09:23:26AM +0000, Matt Bernstein wrote:
>> On Jan 10 2008 J. Bruce Fields wrote:
>>> The easiest thing is probably just to turn off leases:
>>> echo 0 >/proc/sys/fs/leases-enable
>>
>> I found this from two years ago, and am wondering
>> - is this still the easiest thing to do?
>> - is this on server, client or both?
>> - will it break anything else?
>>
>> We have a CentOS 5.4 NFS3/NFS4/samba server with about 300 clients on its
>> subnet, and another 100-200 on another subnet, which under high load has
>> started kernel-panicking (sometimes in nfsd4_cb_recall).
>
> Have you filed a bug with the backtraces?
Duly nudged. I've posted the most recent one to
<http://bugs.centos.org/view.php?id=4229>.
>> I want to disable delegations to see if that cures our symptoms--but I
>> worry that turning leases off might cause other problems.
>
> No, it shouldn't cause problems, at least for NFSv4 clients. (Samba may
> be more reliant on leases, especially if Samba and NFSv4 clients are
> acting on the same files at the same time--but I don't know.)
Thanks; no-one's grumbled just yet.
Matt
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Turning off delegations in NFSv4 server?
2010-03-05 15:12 ` Matt Bernstein
@ 2010-03-05 15:30 ` J. Bruce Fields
0 siblings, 0 replies; 6+ messages in thread
From: J. Bruce Fields @ 2010-03-05 15:30 UTC (permalink / raw)
To: Matt Bernstein; +Cc: NFS list, nfsv4, Matt Bernstein
On Fri, Mar 05, 2010 at 03:12:46PM +0000, Matt Bernstein wrote:
> On Mar 4 J. Bruce Fields wrote:
>> On Thu, Mar 04, 2010 at 09:23:26AM +0000, Matt Bernstein wrote:
>>> On Jan 10 2008 J. Bruce Fields wrote:
>>>> The easiest thing is probably just to turn off leases:
>>>> echo 0 >/proc/sys/fs/leases-enable
>>>
>>> I found this from two years ago, and am wondering
>>> - is this still the easiest thing to do?
>>> - is this on server, client or both?
>>> - will it break anything else?
>>>
>>> We have a CentOS 5.4 NFS3/NFS4/samba server with about 300 clients on its
>>> subnet, and another 100-200 on another subnet, which under high load has
>>> started kernel-panicking (sometimes in nfsd4_cb_recall).
>>
>> Have you filed a bug with the backtraces?
>
> Duly nudged. I've posted the most recent one to
> <http://bugs.centos.org/view.php?id=4229>.
OK, thanks. Unfortunately that code has changed quite a bit since
2.6.18. I don't recall this specific bug, but I wouldn't be suprised if
it's something we've since fixed. Looking through 'gitk v2.6.18..
fs/nfsd/nfs4callback.c fs/nfsd/nfs4state.c' for delegation/callback
fixes might be one approach.
--b.
>
>>> I want to disable delegations to see if that cures our symptoms--but I
>>> worry that turning leases off might cause other problems.
>>
>> No, it shouldn't cause problems, at least for NFSv4 clients. (Samba may
>> be more reliant on leases, especially if Samba and NFSv4 clients are
>> acting on the same files at the same time--but I don't know.)
>
> Thanks; no-one's grumbled just yet.
>
> Matt
^ permalink raw reply [flat|nested] 6+ messages in thread
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2008-01-10 19:57 Turning off delegations in NFSv4 server? Jeff Garzik
2008-01-10 20:00 ` J. Bruce Fields
2010-03-04 9:23 ` Matt Bernstein
2010-03-04 14:33 ` J. Bruce Fields
2010-03-05 15:12 ` Matt Bernstein
2010-03-05 15:30 ` J. Bruce Fields
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