Brad Nicholson <bnichols(at)ca(dot)afilias(dot)info> writes:
> On Tue, 2007-07-10 at 11:19 -0400, Tom Lane wrote:
>> Oh, I forgot to mention --- you did check that vacuum_mem is set to
>> a pretty high value, no? Else you might be doing a lot more
>> btbulkdelete scans than you need to.
> What would you define as high for 7.4? I bumped it up to ~ 245mbs
That sounds like plenty --- you only need 6 bytes per dead tuple,
so that should be enough to handle all your 15-20M dead tuples in
one scan.
How big is this index again?
regards, tom lane