Re: Performances with new Intel Core* processors

On 31-7-2006 17:52, Merlin Moncure wrote:
> On 7/31/06, Jonathan Ballet <jon@multani.info> wrote:
>> Hello,
>>
>> I've read a lot of mails here saying how good is the Opteron with
>> PostgreSQL,
>> and a lot of people seems to recommend it (instead of Xeon).
>
> I am a huge fan of the opteron but intel certainly seems to have a
> winner for workstations. from my research on a per core basis the c2d
> is a stronger chip with the 4mb cache version but it is unclear which
> is a better choice for pg on 4 and 8 core platforms.  I have direct
> personal experience with pg on dual (4 core) and quad (8 core) opteron
> and the performance is fantastic, especially on 64 bit o/s with > 2gb
> memory (vs 32 bit xeon).

As far as I know there is no support for more than two Woodcrest
processors (Core 2 version of the Xeon) in a system. So when using a
scalable application (like postgresql) and you need more than four
cores, Opteron is still the only option in the x86 world.

The Woodcrest however is faster than a comparably priced Opteron using
Postgresql. In a benchmark we did (and have yet to publish) a Woodcrest
system outperforms a comparable Sun Fire x4200. And even if you'd adjust
it to a clock-by-clock comparison, Woodcrest would still beat the
Opteron. If you'd adjust it to a price/performance comparison (I
configured a HP DL 380G5-system which is similar to what we tested on
their website), the x4200 would loose as well. Mind you a Opteron 280
2.4Ghz or 285 2.6Ghz costs more than a Woodcrest 5150 2.66Ghz or 5160
3Ghz (resp.), but the FB-Dimm memory for the Xeons is more expensive
than the DDR or DDR2 ECC REG memory you need in a Opteron.

> also opteron is 64 bit and mature so i think is a better choice for
> server platform at the moment, especially for databases.  my mind
> could be changed but it is too soon right now.  consider how long it
> took for the opteron to prove itself in the server world.

Intel Woodcrest can do 64-bit as well. As can all recent Xeons. Whether
Opteron does a better job at 64-bit than a Xeon, I don't know (our test
was in 64-bit though). I have not seen our Xeon 64-bits production
servers be any less stable than our Opteron 64-bit servers.
For a database system, however, processors hardly ever are the main
bottleneck, are they? So you should probably go for a set of "fast
processors" from your favorite supplier and focus mainly on lots of
memory and fast disks. Whether that employs Opterons or Xeon Woodcrest
(no other Xeons are up to that competition, imho) doesn't really matter.

We'll be publishing the article in the near future, and I'll give a
pointer to it (even though it will be in Dutch, you can still read the
graphs).

Best regards,

Arjen van der Meijden
Tweakers.net