Multicore Is Bad News For Supercomputers

[Axemantitan]

With no other way to improve the performance of processors further, chip makers have staked their future on putting more and more processor cores on the same chip. Engineers at Sandia National Laboratories, in New Mexico, have simulated future high-performance computers containing the 8-core, 16‑core, and 32-core microprocessors that chip makers say are the future of the industry. The results are distressing. Because of limited memory bandwidth and memory-management schemes that are poorly suited to supercomputers, the performance of these machines would level off or even decline with more cores. The performance is especially bad for informatics applications—data-intensive programs that are increasingly crucial to the labs’ national security function.

http://www.spectrum.ieee.org/nov08/6912

http://www.spectrum.ieee.org/images/nov08/images/umult01.jpg

[OceanView]

So 4 is better than 64?
I guess I don't have to buy another computer after I get a 4 core machine.:D

[Trip.Tucker]

So 4 is better than 64?
I guess I don't have to buy another computer after I get a 4 core machine.:D

Do you really need 4 cores?

[Abstract]

^^^I need 40. Actually, I need as many as possible. More cores certainly wouldn't hurt me.

[Arcadie]

well i would take a single core 8GHz CPU over a quad core 2 GHz CPU anyday.
Honestly 4 cores is enough, i rather intel work on bettering processors in other areas besides the number of cores.

[barkmonster]

I'm thinking 4 cores of a high clock speed would be the better option.

http://www.barefeats.com/octopro1.html

This is an article about memory bandwidth that shows an 8 core mac pro only having 350Mb/s per core.

for comparison, on this page

http://barefeats.com/hard103.html

2 fast SSDs raided together achieve 488Mb/s in one of the benchmarks

[iMacmatician]

This just further highlights the importance of the "uncore."

The upcoming Sandy Bridge microarchitecture will supposedly improve interconnections. Intel is also working on memory stacking etc. on CPUs in the far future.

[twoodcc]

interesting. i hope that they figure a way around this. if not, 8 cores is the top

[dukebound85]

me likey my 4 core machine

[wizzracer]

Just one hugh pipe. Say around 1024 lanes, each running up too 1gig bandwidth. Yea that should hold me for a few years.:eek:

Oh yea, give me 1 TB Upload and DL speed too, "For free":D