Sorry, I made an mistake. "Kyotaro HORIGUCHI" <horiguchi.kyot...@lab.ntt.co.jp>:
> Overall algorithm could be illistrated as below, > > - summing up used bytes, max offnum(PageGetMaxOffsetNumber), Not "max" offnum, the number of linp's used after page vacuum. > maximum free bytes for tuple data , and free bytes after page > vacuum through all scanned pages. > > - summing up free bytes informed by FSM through all skipped > pages. > > - Calculate mean tuple length from the overall used bytes and > sum of max offnums, and scanned pages. Here also is the same. not sum of max offnum but total of used entrre(linp)s. > - Guess tuple density in skipped pages using overall free bytes > from FSM and the mean tuple length calculated above. > > - Finally, feed estimated number of the live tuples BEFORE > vacuum into vac_estimate_reltuples. regards, -- Kyotaro Horiguchi