Thread: disk usage advice needed

Hello

My data directory is like (pg 7.1 linux 2.4.4)
---
$ ls
PG_VERSION  base/  global/  pg_hba.conf  pg_ident.conf  pg_xlog/  postgresql.conf  postmaster.opts
----

With 7.0.3 I remember?? that there are files named according to table
names.  With 7.1 I don't know which disk file is associated with
which table.  What I would like to do is spread the files between
two ide disks in order to gain some performance.  I heard
somewhere that I can symlink some of the files to a different
disk to gain some speed and I was wondering of which of those
files are my tables.   What advise would you give if I
can split pg data between two disks.

I think all of the data is in base/ directory and it looks
like this

    1/  18719/  18836/  573216/

I have two currently two big tables that are
constantly (1-5 times per second the whole day)
being accessed and always simultaneously and
I wish these two tables to live on two separately.

Thanks in advance

On Wed, May 02, 2001 at 10:45:09AM -0400, Bruce Momjian wrote:
> > I wish these two tables to live on two separately.
>
> I just wrote two articles, one on performance and the other on writing
> PostgreSQL applications.  You can get them at:
>
>     http://candle.pha.pa.us/main/writings/pgsql/
>

Thank you very much.  Your article was precisely what
I was looking for.  It pointed out to me that I need this
query
    select relfilenode,relname from pg_class where relname !~ '^pg';

Regards

> Hello
>
> My data directory is like (pg 7.1 linux 2.4.4)
> ---
> $ ls
> PG_VERSION  base/  global/  pg_hba.conf  pg_ident.conf  pg_xlog/  postgresql.conf  postmaster.opts
> ----
>
> With 7.0.3 I remember?? that there are files named according to table
> names.  With 7.1 I don't know which disk file is associated with
> which table.  What I would like to do is spread the files between
> two ide disks in order to gain some performance.  I heard
> somewhere that I can symlink some of the files to a different
> disk to gain some speed and I was wondering of which of those
> files are my tables.   What advise would you give if I
> can split pg data between two disks.
>
> I think all of the data is in base/ directory and it looks
> like this
>
>     1/  18719/  18836/  573216/
>
> I have two currently two big tables that are
> constantly (1-5 times per second the whole day)
> being accessed and always simultaneously and
> I wish these two tables to live on two separately.

I just wrote two articles, one on performance and the other on writing
PostgreSQL applications.  You can get them at:

    http://candle.pha.pa.us/main/writings/pgsql/

--
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 853-3000
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