MacBook Pro speed comparisons

[mactrue]

I have 2 nearly identical 15" macbookpro laptops. One was purchased on Jun 24, 2011 ( Order # , snow leopard), and the second on Nov 03, 2011 (Order # Lion), . Both machines have the intel 2.2 GHz quad-core i7 processor. Every effort was made to make these two machines identical. But the first machine runs about 3 times faster than the second. I do very computationaly intensive runs that solve mathematical equations through thousands of iterations that may last 3 or 4 days. The slower machine would take 9 to 12 days.
When I set up my first macbookpro, one question asked was "When I do intense computations, do I want to distribute the workload among the cores?" I answered YES. But the setup for my second (slower) machine never asked that question. The difference in speeds is too dramatic to attribute it to snow leopard vs Lion.
What do I need to do to make my second machine run as fast as my first to take full advantage of the processor?

 

[mrapplegate]

I have 2 nearly identical 15" macbookpro laptops. One was purchased on Jun 24, 2011 ( Order # W298044308, snow leopard), and the second on Nov 03, 2011 (Order # W296159812 Lion), . Both machines have the intel 2.2 GHz quad-core i7 processor. Every effort was made to make these two machines identical. But the first machine runs about 3 times faster than the second. I do very computationaly intensive runs that solve mathematical equations through thousands of iterations that may last 3 or 4 days. The slower machine would take 9 to 12 days.
When I set up my first macbookpro, one question asked was "When I do intense computations, do I want to distribute the workload among the cores?" I answered YES. But the setup for my second (slower) machine never asked that question. The difference in speeds is too dramatic to attribute it to snow leopard vs Lion.
What do I need to do to make my second machine run as fast as my first to take full advantage of the processor?

What asked you this:
"When I do intense computations, do I want to distribute the workload among the cores?"

The key it seems to be with what software asked you that. I've never seen such a question from my many years of Mac ownership, so I'm going to assume it was not the operating system.


Each application has to be written to take advantage of multiple cores, so what software is not working well for you.

 

[mactrue]

Thanks for responding. The question was asked as I was initially setting up the macbook pro out of the box. At that point, I had not installed any software of my own at all. I have asked the same question at an Intel forum, but there has been no reply.

 

[robvas]

Thanks for responding. The question was asked as I was initially setting up the macbook pro out of the box. At that point, I had not installed any software of my own at all. I have asked the same question at an Intel forum, but there has been no reply.

I've set up a ton of macs and never seen this!

 

[mactrue]

I'm still trying to understand how two nearly identical laptops can have such a significant difference in speed. The fast machine is acting as if some paralelization code has been activated for the simulations that I run, but I haven't installed any such code.

 

[joshhedge]

I'm still trying to understand how two nearly identical laptops can have such a significant difference in speed. The fast machine is acting as if some paralelization code has been activated for the simulations that I run, but I haven't installed any such code.

A simple suggestion, that could work, would be to reset the SMC and PRAM of the under performing machine. That is where my technical knowledge drops off I'm afraid.

 

[fskywalker]

What comes to my mind could be RAM memory speed; very likely that the faster one has a faster RAM than the other one.

 

[joshhedge]

What comes to my mind could be RAM memory speed; very likely that the faster one has a faster RAM than the other one.

They're the same model so the RAM, given that OP hasn't changed it himself, should have the same frequency and timings.

 

[fskywalker]

not necessarly, it could depend on availability at the time of assembly.

 

[duervo]

What happens when you take the drive out of the faster system, and boot the slower system from it?

If the slower system runs faster from that drive, then it most likely points to a software issue.

If it runs slower, then it points to hardware, assuming firmware levels and all other aspects equal.

You can also rule out RAM by swapping them between systems and comparing.

 

[adnbek]

Open activity monitor on each when running the task and look at the cpu usage graphs at the bottom. Are all 4 cores being maxed out on both machines?

Also, install a temperature monitoring program and see what temps you're getting on both. The CPU on the slower one might be throttling due to higher temps.

 

[mactrue]

Thanks for all the suggestions. I'll give them all a try.
I've watched the activity monitor on the slow machine, and all cores are being used. None of them are maxed out. I'll install the temperature monitor to see what that shows.