On Tue, 2006-11-07 at 11:19 -0600, Fletcher Mattox wrote: > Jeff Moyer writes: > > > http://people.redhat.com/jmoyer/autofs_linux_kongress.pdf > > Jeff, > > Nice paper. Thanks! I'm suffering from RPC port exhaustion (you > responded to one of my queries last week), so I am especially interested > in your section on port allocation. You state > > When a service requests an RPC connection, binding to > a reserved port is the default. The RPC layer scans > ports starting from 800 down until it finds one that > is unallocated. > > My experience is that the 2.6.17.4 kernel allocates between 512 and 1024 > and then begins with unreserved ports >33000. Yeah, I know. It's just > a nit, but I thought I'd tell you anyway.
We know there have been changes in that area but I don't think they were in place at the time this was written. However, the changes were in place when the paper was updated and that section wasn't updated. Bit naughty really. The updated version is in the 2006 OLS publication. > > The most interesting part of the paper was the comment about a practical > limit of 100 mounts in rapid succession. I am certain this is the limit > we have bumped into. Do you see any improvement in this in autofs 5? Not really, about 3/4 of the additional port opens are done in mount, not autofs. > > Unprivileged ports and/or UDP are not viable options for us, so I am > forced to increase the timeout from 5 minutes to 24 hours, which in > practice means they are always mounted. We have about 400 automounted > filesystems, so the only long term solution for us is to try to coalesce > them to less than 100. Very painful. Understood. We had similar constraints at my last employer. I'm not aware of any work being actively done on this. Nobody that cares has any time at the moment. Ian _______________________________________________ autofs mailing list [email protected] http://linux.kernel.org/mailman/listinfo/autofs
