Re: What is the long term fix for the idmapper key-quota problem.

[Anna Schumaker <bjschuma@netapp.com>]

On Mon 21 Oct 2013 01:05:14 AM EDT, NeilBrown wrote:
>
> Hi,
>  as you probably know, request_key() imposes a quota on
> the number of keys that can be requested, which by default is quite low (200).
> When idmap exceeds this quota, request_key() returns an error and
> the result is userspace sees "nobody" as the owner.
>
> A short term fix is to fiddle some sysctl values, but I wonder if any long
> term fix is being planned.

I don't have anything planned.

>
> Probably the sensible thing would be for nfs-idmap to bypass the quota.
> As keys are not held active for very long at a time, they should be garbage
> collected in due course.
> There is currently no interface to request this but I suspect one could be
> added.

Adding a new keyring interface might be a better question for David 
Howells, since he's done a lot of keyring work.

How many idmap keys do you have active at once?  I'm guessing the quota 
is there for a reason, and increasing it in-kernel would probably be 
much easier than adding a new interface for short-lived keys.

>
> (I want to fixed this for openSUSE-13.1, and don't want to diverge too far
> from mainline).
>
> Thanks,
> NeilBrown