"witness_lock_list_get: witness exhausted"

John Baldwin jhb at freebsd.org
Thu Aug 18 17:11:05 UTC 2011

On Tuesday, August 16, 2011 5:59:53 pm Peter Jeremy wrote:
> I'm getting the above message when running Peter Holm's stress
> test with INCARNATIONS=150 on a 16-core sparc.  Does this mean
> LOCK_CHILDCOUNT is too low or does it indicate a leak in witness
> lock_list_entry's somewhere?

Most likely the former.

> The comment on LOCK_CHILDCOUNT indicates it is dimensioned to
> allow 2048 threads to hold 5 locks each but it's not clear how
> many threads will get started at a given INCARNATIONS count.

Also, each lle holds a bucket of instances, so the same count
would only let 1024 threads hold 6 locks each perhaps (depending
on the bucket size.. it was originally 4 locks per lle).

John Baldwin

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