> > Quite a few people have reported finding the opposite in practice.
> > You should probably try vacuuming after deleting or updating some
> > fraction of the rows, rather than just the all or none cases.
> >
>
> Vacuum after delelting all rows isn't a worst case.
> There's no moving in that case and vacuum doesn't need to call
> index_insert() corresponding to the moving of heap tuples.
>
> Vacuum after deleting half of rows may be one of the worst case.
> In this case,index_delete() is called as many times as 'delete all'
> case and expensive index_insert() is called for moved_in tuples.
I will test that.
-- Bruce Momjian | http://www.op.net/~candle pgman@candle.pha.pa.us | (610)
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