proposed PAG handling changes for Arla

[Chris Wing]

Assar:

> Yes, `fs gcpags' will do a pioctl VIOC_GCPAGS.  (Which is a nop in
> Arla :-)

Oops, I guess I should have read more of the code before commenting :)
> 
> > In Arla, it's less of an issue since the tokens are stored in user
> > space, not kernel space. (arlad does all the real work)
> 
> Yes.  Expanding on this a little bit, arlad stores the credentials of
> the actual users in a hash table from which credentials get deleted
> when you do `unlog' or when the credential expires.

I've seen arlad messages in the syslog when tokens expire, and I've
noticed the credentials cache in the code.

So does the official AFS never get rid of tokens or PAG data structures
unless there is always an explicit unlog? We run some pretty big login
servers around here that use the latest 'official' AFS on Solaris or
HP-UX, and I haven't noticed them being particularly slow to setpag(),
despite long uptimes and the fact that most of the users don't unlog
before logging out.

-Chris
wingc at engin.umich.edu