If HOT gets into 8.3, we might need a GUC to set database wide heap
fillfactor to an appropriate value. The only way to so today is compile
time value of DEFAULT_HEAP_FILLFACTOR. HOT works much
better if there is atleast one tuple worth of free space in each block.
Otherwise atleast the first UPDATE in each block would be a COLD
Should we consider adding such a GUC now ? I searched through
archives, but did not find any strong objection to doing so in the past.
But I might have missed something. Comments ?