Multitasking with Conroe

[mmj_uk]

Seem to be a lot of reports that, despite the awesome singlethreaded performance Conroe isn't so hot for multitasking due to the shared cache; and that when multithreading and 64bit finally takes off Conroe will struggle compared to its AMD counterparts?

http://sharikou.blogspot.com/2006/04/conroe-performance-claim-being-busted.html

The reason why Conroe did so well in the MolDyn test is simple: Conroe has a huge 4MB of unified cache, for such single threaded tests that can fit in 4MB*, Conroe can just run off the cache with very high speed. Since cache misses drastically reduce peformance, applications run off cache exhibit unrealistic performance numbers.

I guess that explains the insane superpi times?

However, once you go over the 4MB limit, Conroe is slower than Athlon 64 at the same clock. Both the Cryptography and STREM tests use a lot more than 4MB, larger than Conroe's 4MB cache, and Conroe immediately falls below Athlon 64 on the performance curve.

The conclusion is: clock for clock, Athlon 64 will beat Conroe in real application environments that require a working set of larger than 4MB, or in other words, larger than Conroe's 4MB cache. This means in any real multi-tasking or server environment the Core architecture will be an underdog. Even worse, for Intel's shared cache architecture, cache thrashing is a distinct possibility under heavy loads.

So have we all been conned by Intel?

I mean you buy Conroe and the new Intel quad core for multitasking and as a future proof option for multithreaded games so it's a bit of a con if they turn out to be lemons under those circumstances.

http://www.google.co.uk/search?hl=en&q=conroe+multitasking&meta=