I am about to pull the trigger on a new machine after analyzing some
discussions I posted here last year. I've been trying to spec out a reliable
and powerfull enough machine where I won't have to replace it for some time.
Currently I've been using a dual Xeon 3.06ghz with 4GB of ram and utilizing a
RAID 1+0 configuration over a total 6 SCSI disks asside from the OS partition.
We have about 10GB of data and will probably scale at about 1GB per month. We
currently average about 200 queries per second and the 15 minute load average
is about .30. I am running FreeBSD 6.1.
At the end of last year, I specced out a new machine to replace this box. At
that time, the quad core 2.66ghz were not available from my vendor and I was
not planning to go that route. Now that they are available, I am considering
the option. The main question here is whether FreeBSD 6.X and PostgreSQL 8.1
would be able to take advantage of the quad core and perform better than the
3.0Ghz dual core. The reason I ask is due to some conflicting benchmarking
results I see posted on the spec.org website.
Here is the full specification of the new box I hope to build and run FreeBSD
6.X and PostgreSQL on:
- SuperMicro Dual Xeon X7DBE+ motherboard
+ 2 x Quad Core X5355 2.66Ghz
OR
+ 2 x Dual Core 5160 3.0Ghz
- 8 x 1GB PC2-4200 fully buffered DIMM
- LSI MegaRAID SAS 8408E w/BBU 256MB
- 16 x 73GB SAS disk
So, question #1, to go dual core or quad core? Quad core in theory seems to
scale the machine's processing potential by almost a factor of two.
We recently migrated from a four way opteron @ 2 GHz with 8 GB to a
four way woodcrest @ 3 GHz (HP DL380 G5) with 16 GB ram. I also
upgraded FreeBSD from 6.0 to 6.2 and did a minor upgrade of postgresql
from 7.4.9 to 7.4.12. The change was tremendous, the first few hours
of after it went into production I had to doublecheck that our website
worked, since the load was way below 1 whereas the load had been
almost 100 during peak.
I don't have any financial ties to HP but building a server from
scratch may not be worth it, rather than spending time assemling all
the different parts yourself I would suggest you get a server from one
vendor who build a server according to your specs.
The DL380 (also) has a 256 MB bbc controller, the nic works flawlessly
with FreeBSD 6.2, all parts are well integrated, the frontbay can
accomodate 8 146 GB SAS drives. This server is wellsuited as a
postgresql-server.
Approx. 200 reqest a sec. should be a problem unless the queries are heavy.
regards
Claus
