Обсуждение: Stats not getting updated....

i am trying to identify which tables should be moved to diff drives.... i first identified the most used tables... by looking at the data in pg_statio_user_tables.....

and then i did sampling of the io-usage of these tables every 2 mins... to identify which are getting used when....

 

but the problem is my stats are not getting updated.... they first get updated around 20% done... and then once more at around 70% done.... why is the stats not getting updated more frequently.....

 

the test application i am using has a 33 min test with lots of read and write....

 

thx

Himanshu

Himanshu Baweja wrote:
> i also noted one more thing... the stats are getting updated only
> when i do vacuum.... is that wht is supposed to happen... or
> something is wrong....

Hmm - there's something strange going on certainly. Try a couple of
simple queries on a table and see whether the stats get updated.

It is possible that during very busy periods the stats don't get
recorded - that's part of the design.

--
   Richard Huxton
   Archonet Ltd

Richard Huxton <dev@archonet.com> writes:
> It is possible that during very busy periods the stats don't get
> recorded - that's part of the design.

IIRC, backends only ship stats to the collector at transaction commit.
Or maybe it's at the end of processing a client command.  It's certainly
not continuous.

            regards, tom lane