Re: ANALYZE sampling is too good

On 12/6/13 3:21 AM, Andres Freund wrote:
> On 2013-12-05 17:52:34 -0800, Peter Geoghegan wrote:
>> Has anyone ever thought about opportunistic ANALYZE piggy-backing on
>> other full-table scans? That doesn't really help Greg, because his
>> complaint is mostly that a fresh ANALYZE is too expensive, but it
>> could be an interesting, albeit risky approach.
>
> What I've been thinking of is
>
> a) making it piggy back on scans vacuum is doing instead of doing
> separate ones all the time (if possible, analyze needs to be more
> frequent). Currently with quite some likelihood the cache will be gone
> again when revisiting.

FWIW, if synchronize_seqscans is on I'd think it'd be pretty easy to fire up a 2nd backend to do the ANALYZE portion
(orperhaps use Robert's fancy new shared memory stuff).
 
-- 
Jim C. Nasby, Data Architect                       jim@nasby.net
512.569.9461 (cell)                         http://jim.nasby.net