Brad Nicholson <bnichols(at)ca(dot)afilias(dot)info> writes:
> We have been having a problem with a long running vacuum on a table 
> blocking deletes.  We have a log table on which the only activity is an 
> on going series of deletions.  The problem is experienced on a slony 
> replicated node, but I don't  think that slony is at fault here.

> My question - why is a vacuum blocking a deletion?

The problem is evidently that it's got an exclusive lock on the table:

>     17578 | 1744920 | AccessExclusiveLock      | t

which is entirely unexpected behavior for plain VACUUM in any release
later than 7.1.  I have to think that slony does have something to do
with it ... would suggest asking the slony folk about this.

			regards, tom lane

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• Vacuum Blocking A Deleteion - Why? at 2006-01-04 21:23:05 from Brad Nicholson

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