Re: TSearch: CLUSTER using GIST, query using GIN?

On Sat, 19 Jan 2008, Hannes Dorbath wrote:

> Does it make any sense to CLUSTER by a GIST index to move tuples with similar
> lexems physically closer together on disc, drop it and use GIN for the actual
> queries?
>
> My queries are bound by HDD seek speed currently, might the above help me or
> can it even be counterproductive?

what do you want to speed up ? Search is very fast, see explain analyze.
The problem usually in the access to documents found to calculate
rank, headlines. If GIN returns N documents, then you need to read
all of them to calculate rank and here you get slowdown.

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru)
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83