Re: Non-linear Performance

I have my Dual P4-Xeon 2.4 ghz 8gb RAM Adaptec SCSI RAID 5 PostgreSQL
server coming in Friday, from my vendor POGO Linux (highly recommended). I
expect most of the 8gb to be used by buffer cache directly by the operating
system. I will let you know how it compares to the dual P3-1ghz 2GB IDE
RAID 1 server we use now.

The server cost just over half the price of a DB2 enterprise single-CPU
license. Thank god for Postgres!

My biggest fear is that the added CPU speed will be sub-linear, and that
the real speed improvement would come if PG would multi-thread individual
queries.

Cheers,

Doug

At 11:42 PM 6/7/2002, Peter A. Daly wrote:
>Bruce Momjian wrote:
>
>>
>>I am curious how you are going to address >4 gig of RAM on a 32-bit
>>system, especially if you want to address it all from the same process.
>Frankly, I don't know. I have been told the machine can hold 8 gig of
>ram. I have heard rumors about how Linux plays some games with how it
>allocates memory to use over 4 gigs of memory. but have no direct
>knowledge myself of the matter. Something alongs the lines of a single
>process being able to use up to 4 gig of memory. Not sure on the
>specifics. Looks like we will not be upgrading the database server for at
>least another 60 days (the postgres one at least), and the dual Xeon (Quad
>soon?) may have another purpose. We have a 1.5tb file server/image
>rendering machine that is out of space for expansion. The Xeon has enough
>PCI slots to let us add more RAID arrays for a lot longer, where the
>current server is out of slots. This being the case, I have stopped
>trying to milk speed out of postgres on that machine.
>
>On the positive side of this, I may get a higher end Quad Xeon after July
>for the next Postgres box. We have our eyes on Quad 700mhx Xeon, 8gig ram
>boxes.
>
>-Pete
>
>
>
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