Seti@Home optimized science apps and information

Optimized Seti@Home apps => Linux => Topic started by: michael37 on 30 Jun 2007, 12:40:24 am

Title: Core 2 app working on non-Core 2 CPU?
Post by: michael37 on 30 Jun 2007, 12:40:24 am

Quick question to expert community.  I got hands on a quad-Dempsey.  Nice system with HT enabled, makes up 8 processors.  It's marketed as Intel 50XX family of processors, and it's a last family preceding Core 2-based Woodcrests (aka 51xx family).  It's definitely not a Core 2.

So, I tried running the SSSE3 app and it completed the test workunit faster than any other app.  Then, I ran iit for a few days and it had no problems running nor validating workunits.

Am I missing something?  Isn't Core 2 app supposed to break on non Core-2 CPUs?  I am running

Optimized SETI@Home Enhanced application
Optimizers: Ben Herndon, Josef Segur, Alex Kan, Simon Zadra
Linux port: Crunch3r, Hans Dorn, Simon Zadra
   Version: Linux 64-bit based on S@H V5.15  'Noo? No - Ni!'
  Revision: R-2.2B|xT|FFT:IPP_SSSE3|Ben-Joe
     CPUID:                   Intel(R) Xeon(TM) CPU 3.40GHz
      CPUs: 2, cores: 1,  cache: L1=16K,  L2=1024K, L3=16384K
  Features: MMX  SSE  SSE2  SSE3  SSSE3 x86_64 

If anyone wants to look, here is link (http://setiathome.berkeley.edu/show_host_detail.php?hostid=3495658) to this host. 

Title: Re: Core 2 app working on non-Core 2 CPU?
Post by: Simon on 30 Jun 2007, 01:13:35 am

Hm,

until now I thought there was only one ill-fated - and never commercially released - pre-Core 2 CPU that supported SSSE3, and that's the "Tejas". PD-descendant, large caches, slightly better power consumption than 9xx PDs, but no match for Opterons at the time.

So either Intel decided to market them as 50xx and I missed that, or something strange is going on :)

Regards,
Simon.

Title: Re: Core 2 app working on non-Core 2 CPU?
Post by: michael37 on 30 Jun 2007, 11:26:05 am

It's strange indeed.  Notably, and expectedly, the higher clock speed (3.4GHz) Dempsey based on Netburst technology performs slower than my Core 2 Woodcrest at 2.66GHz.    At 8 CPUs though, the total RAC is not bad.

I wish I had some quad cores for apples to apples 8-way comparison.