What is the NFS max thread limit

[Eric Browning]

I'm currently still debugging slow NFS performance on mac clients.  Running
9 stable with a mix of 200 Mac OS X 10.8, 10.7 and 10.6 clients.

Periodically I get this error on the mac side:
automountd[1766]: set_and_fake_mapent_mntlevel: subdir=/Contents error:
Contents not found in map=-fstab

I'm wondering with 200 clients with five nfsiod threads (~1000 nfsiod
threads total) am I oversubscribing the nfs server?  I can't seem to
configure any more than 256 threads (nfs_server_flags="-t -n 256").  When I
configure above 256 I get an error about it resetting to 4:

Starting nfsd.
nfsd: nfsd count 512; reset to 4

Tomorrow when all the mac clients have restarted I have changed their
nfsiod threads down to 1 each to see if this is indeed the issue.

Thanks in advance,
-- 
Eric Browning
Systems Administrator
801-984-7623

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