Broadening the scope of the negative connection cache

[Marc VanHeyningen]

I've encountered some minor performance in Samba that come up when a PDC
is down.  Briefly, the ability of the negative connection cache to limit
the time wasted attempting to contact that PDC is limited by the fact
that it's implemented as a linked list and limited in scope to the
process where the failed connection was performed.

 

The obvious solution would be to migrate the negative connection cache
to be stored in a different way, probably as a TDB file.  This would
allow every child process to share the failure information.

 

I guess the questions are: Does this make sense?  If so, should this be
a wholesale replacement or conditional on something like #ifdef
CONNCACHE_USING_TDB?  I can't really imagine that the performance
considerations would be so great that anyone would want to revert to the
old way.

 

Thanks!

Marc