Re: tsearch2: very slow queries - Mailing list pgsql-general

From Oleg Bartunov
Subject Re: tsearch2: very slow queries
Date
Msg-id Pine.GSO.4.63.0508081128130.10571@ra.sai.msu.su
Whole thread Raw
In response to Re: tsearch2: very slow queries  ("Marc G. Fournier" <scrappy@postgresql.org>)
List pgsql-general
Hi there,

tsearch2 is our next problem we plan to attack after we have done with
GiST core. Actually, we did some experiments in background and we're sure we
could very greatly improve tsearch2 performance and  add a lot of nice
features. Most probably, we'll call for fund raising for this project
as soon as we find out how to reliably transfer money to us.

     Oleg

On Sun, 7 Aug 2005, Marc G. Fournier wrote:

> On Sun, 7 Aug 2005, Joshua D. Drake wrote:
>
>> Marc G. Fournier wrote:
>>>
>>> 'k, I'm obviously doing something wrong, since my experiences with sites
>>> like fts.postgresql.org indicate things should be *alot* faster then I'm
>>> getting ...
>>
>> Well the first thing I would ask is are you running 8.0? My testing shows
>> that Tsearch is pretty abysmal if you are not running 8.0. At least with
>> very large tables.
>
> This is one thing I was fearing, especially with the work that Teodor and
> gang have been putting into it for 8.1 :(  Unfortunately, we're currently
> stuck with 7.4.6 for this, so that is one thing I'm going to have to take
> into consideration ...
>
>> Considering the number of rows I am not that surprised but I would be
>> curious to know what type of HD you have? Also correct me if I am wrong but
>> gist indexes are typically very large. Do you have enough work_mem/sort_mem
>> to keep them from going to disk?
>
> I'm currently playing in a non-production environment (ie. my desktop
> machine) just to get a feel for things ... our main server for this is a
> proper 4G of RAM, sort_mem bump'd up quite nicely, and file system spread
> over multiple spindles ...
>
> Right now, I'm just playing with / learning the tsearch stuff, so am more
> looking at a 'this is the worst case scenario on my box', and this improves
> things ... not perfect, but anything I can improve here, I know will be
> easier to improve on the production server :)
>
> ----
> Marc G. Fournier           Hub.Org Networking Services (http://www.hub.org)
> Email: scrappy@hub.org           Yahoo!: yscrappy              ICQ: 7615664
>
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     Regards,
         Oleg
_____________________________________________________________
Oleg Bartunov, sci.researcher, hostmaster of AstroNet,
Sternberg Astronomical Institute, Moscow University (Russia)
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(095)939-16-83, +007(095)939-23-83

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