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* Can Postgres cache a table in memory?
@ 2002-10-03 14:03 Kevin Traub <ktraub@verizon.net>
0 siblings, 4 replies; 5+ messages in thread
From: Kevin Traub @ 2002-10-03 14:03 UTC (permalink / raw)
To: pgsql-sql
Hello all;
I'm trying to speed up a query which returns the majority of a table so and
index isn't helpful.
I've got more than enough RAM to hold my table so, can anyone tell me if
there is there a way to force Postgres to cache a table in RAM?
Any help would be appreciated.
Thanks;
-Kevin Traub
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Can Postgres cache a table in memory?
@ 2002-10-04 13:14 Achilleus Mantzios <achill@matrix.gatewaynet.com>
parent: Kevin Traub <ktraub@verizon.net>
3 siblings, 0 replies; 5+ messages in thread
From: Achilleus Mantzios @ 2002-10-04 13:14 UTC (permalink / raw)
To: Kevin Traub <ktraub@verizon.net>; +Cc: pgsql-sql
On Thu, 3 Oct 2002, Kevin Traub wrote:
> Hello all;
>
> I'm trying to speed up a query which returns the majority of a table so and
> index isn't helpful.
> I've got more than enough RAM to hold my table so, can anyone tell me if
> there is there a way to force Postgres to cache a table in RAM?
>
> Any help would be appreciated.
You need to tune first of all shared_buffers.
Change the postgres.conf file usual in $PGDATA directory.
Bare in mind that one buffer holds 8k of data.
>
> Thanks;
> -Kevin Traub
>
>
>
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==================================================================
Achilleus Mantzios
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IT dept
Dynacom Tankers Mngmt
Nikis 4, Glyfada
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Greece
tel: +30-10-8981112
fax: +30-10-8981877
email: achill@matrix.gatewaynet.com
mantzios@softlab.ece.ntua.gr
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Can Postgres cache a table in memory?
@ 2002-10-04 13:35 Richard Huxton <dev@archonet.com>
parent: Kevin Traub <ktraub@verizon.net>
3 siblings, 0 replies; 5+ messages in thread
From: Richard Huxton @ 2002-10-04 13:35 UTC (permalink / raw)
To: Kevin Traub <ktraub@verizon.net>; pgsql-sql
On Thursday 03 Oct 2002 3:03 pm, Kevin Traub wrote:
> Hello all;
>
> I'm trying to speed up a query which returns the majority of a table so and
> index isn't helpful.
> I've got more than enough RAM to hold my table so, can anyone tell me if
> there is there a way to force Postgres to cache a table in RAM?
You're probably just as well off if you let your OS deal with caching the
underlying file. What figures are you getting (use the "free" command if in
linux). It might be that you've given Postgresql *too* much memory, and
that's interfering with your OS.
Could you provide brief hardware specs, the size of the table concerned, time
taken?
--
Richard Huxton
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Can Postgres cache a table in memory?
@ 2002-10-04 14:14 Tom Lane <tgl@sss.pgh.pa.us>
parent: Kevin Traub <ktraub@verizon.net>
3 siblings, 0 replies; 5+ messages in thread
From: Tom Lane @ 2002-10-04 14:14 UTC (permalink / raw)
To: Kevin Traub <ktraub@verizon.net>; +Cc: pgsql-sql
"Kevin Traub" <ktraub@verizon.net> writes:
> I'm trying to speed up a query which returns the majority of a table so and
> index isn't helpful.
> I've got more than enough RAM to hold my table so, can anyone tell me if
> there is there a way to force Postgres to cache a table in RAM?
There is no need to do anything; if you're hitting the table a lot, it
should all migrate into kernel disk buffers.
regards, tom lane
^ permalink raw reply [nested|flat] 5+ messages in thread
* Re: Can Postgres cache a table in memory?
@ 2002-10-04 15:34 Josh Berkus <josh@agliodbs.com>
parent: Kevin Traub <ktraub@verizon.net>
3 siblings, 0 replies; 5+ messages in thread
From: Josh Berkus @ 2002-10-04 15:34 UTC (permalink / raw)
To: Kevin Traub <ktraub@verizon.net>; pgsql-sql
Kevin,
> I'm trying to speed up a query which returns the majority of a table
> so and
> index isn't helpful.
> I've got more than enough RAM to hold my table so, can anyone tell me
> if
> there is there a way to force Postgres to cache a table in RAM?
Please join the PGSQL-PERFORMANCE mailing list and post this question
there:
pgsql-performance-request@postgresql.org
message: "subscribe"
-Josh Berkus
^ permalink raw reply [nested|flat] 5+ messages in thread
end of thread, other threads:[~2002-10-04 15:34 UTC | newest]
Thread overview: 5+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2002-10-03 14:03 Can Postgres cache a table in memory? Kevin Traub <ktraub@verizon.net>
2002-10-04 13:14 ` Achilleus Mantzios <achill@matrix.gatewaynet.com>
2002-10-04 13:35 ` Richard Huxton <dev@archonet.com>
2002-10-04 14:14 ` Tom Lane <tgl@sss.pgh.pa.us>
2002-10-04 15:34 ` Josh Berkus <josh@agliodbs.com>
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