On Friday May 14 2004 11:47, Jeffrey W. Baker wrote: > > Is there a way to identify the numbers of unused tuples without > > performing a VACUUM? Is it stored in a system table anywhere? Other > > ideas on how to identify disk bloat short of forcing downtime? > > You can calculate the number of bytes per row, multiply by the number of > live tuples (count(1) from table), and subtract that from the actual # > of bytes in the on-disk representation. The difference is wasted space. That works, but with umpteen clusters to manage, I'm really hoping for a SQL-based check so it can be done remotely and non-interactively. Maybe it is too much to keep track of, but it would be cool if VACUUM updated a system table with the same info it spits out during verbose mode. That would be very helpful in auto-identifying leakage and also a recent case where the cpu:real time ratio during vacuum went thru the roof due to I/O overload from leakage. ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
