Martijn van Oosterhout <kleptog(at)svana(dot)org> writes:
> You could do the jump-back-in-blocks only if more than 30% of the table is
> empty and table is over 1GB. For the example here, a simple defragging
> algorithm would suffice; start at beginning and pack each tuple into the
> beginning of the file. It will move *every* tuple but it's more cache
> friendly. It's pretty extreme though.
And your evidence that it will actually be faster is ... ?
regards, tom lane