That is what I wanted to know, how to get the evidence for next time.
Tom Lane wrote:
> Joseph Shraibman <jks@selectacast.net> writes:
>
>>Why then when I did a kill -INT on the vacuuming backends did everything
>>unfreeze?
>
>
> You could have had other stuff backed up behind the VACUUM FULL lock
> requests.
>
> It's not impossible that you had a deadlock *outside* the database,
> that is some wait loop that is partially within and partially outside
> the DB. But if you want me to believe there's a bug in our deadlock
> detector, you're going to have to offer some actual evidence...
>
> regards, tom lane