Re: Performance on new 64bit server compared to my 32bit desktop

Hi!

Thanks for the review link!

Ildefonso.

On Mon, Aug 30, 2010 at 6:01 PM, Greg Smith <greg(at)2ndquadrant(dot)com> wrote:
> Clemens Eisserer wrote:
>
> Hi,
>
>
>
> This isn't an older Opteron, its 6 core, 6MB L3 cache "Istanbul".  Its not
> the newer stuff either.
>
>
> Everything before Magny Cours is now an older Opteron from my perspective.
>
>
> The 6-cores are identical to Magny Cours (except that Magny Cours has
> two of those beast in one package).
>
>
> In some ways, but not in regards to memory issues.
> http://www.anandtech.com/show/2978/amd-s-12-core-magny-cours-opteron-6174-vs-intel-s-6-core-xeon/2
> has a good intro.  While the inside is like two 6-core models stuck
> together, the external memory interface was completely reworked.
>
> Original report here involved Opteron 2427, correctly idenitified as being
> from the 6-core "Istanbul" architecture.  All Istanbul processors use DDR2
> and are quite slow at memory access compared to similar Intel Nehalem
> systems.  The "Magny-Cours" architecture is available in 8 and 12 core
> variants, and the memory controller has been completely redesigned to take
> advantage of many banks of DDR3 at the same time; it is far faster than two
> of the older 6 cores working together.
>
> http://en.wikipedia.org/wiki/List_of_AMD_Opteron_microprocessors has a good
> summary of the models; it's confusing.  Quick chart showing the three
> generations compared demonstrates what I just said above using the same
> STREAM benchmarking that a few results have popped out here using already:
>
> http://www.anandtech.com/show/2978/amd-s-12-core-magny-cours-opteron-6174-vs-intel-s-6-core-xeon/5
>
> Istanbul Opteron 2435 in this case, 21GB/s.  The two Nehelam Intel Xeons,
>>31GB/s.  New Magny, 49MB/s.
>
> --
> Greg Smith 2ndQuadrant US Baltimore, MD
> PostgreSQL Training, Services and Support
> greg(at)2ndQuadrant(dot)com www.2ndQuadrant.us
>