Re: Hardware selection

On Fri, 2003-07-25 at 07:42, psql-mail@freeuk.com wrote:
> As mentioned previously I have a large text database with upwards of
> 40GB of data and 8 million tuples.
>
> The time has come to buy some real hardware for it.
>
> Having read around the subject online I see the general idea is to get
> as much memory and the fastest I/O possible.
>
> The buget for the server is approx 20K GBP / 30K US$
>
> The data will be stored on an external raid,
> SCSI based 2.5TB with IDE disks. Configured as 1 large volume, RAID5. (
> We already have this hardware)

There's a SCSI-IDE bridge somewhere in there?

40GB of data, and 2.5TB disk space??  Even with RAID1+0, that's
1.25TB usable; 40GB (even after accounting for overhead and indexes)
would get lost in 1250GB.  Planning for growth, or also storing lots
of non-DB related files (which is not a good idea)?

> Question 1 - whats the best raid configuration for this device?

What's your read-to-write ratio?

Few complex multi-table queries, lots of simple queries, or
a mixture?

> Onto the server, I have currently priced up the following:
> Dell Poweredge 6650
> 16GB RAM
> Quad intel hyperthreaded arch
> PERC3Q controller
> 36GB System HDD
> approx 20K UKP

Because of the limits of the x86 architecture, with 16GB RAM, I'd
really think about a 64 bit system.  Opteron, Alpha, Power5,
Sparc64, etc.

You can put 16GB RAM in x86 systems, but 64 bit systems use it
more efficiently.

> Question 2 - Comments and opinions on this as the postgresql server.
> Any comments on better alternatives or modification to this system
> would be very helpful!
>
> Question 3 - what would be the best way to distribute tables/swap/
> system disk space?

16GB swap would fit nicely on the system disk.  Hope it's on a
separate channel from the DB...

What OS are you using?

> Hope I'm not asking too much...
> Thanks !

--
+-----------------------------------------------------------------+
| Ron Johnson, Jr.        Home: ron.l.johnson@cox.net             |
| Jefferson, LA  USA                                              |
|                                                                 |
| "I'm not a vegetarian because I love animals, I'm a vegetarian  |
|  because I hate vegetables!"                                    |
|    unknown                                                      |
+-----------------------------------------------------------------+