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selenic

macrumors newbie
Original poster
Oct 11, 2012
3
0
Hi folks, it is my first post (me being a linux/windows user recently starting to use Macs).

I have one MacBook pro (10.6.8), 4GB Ram, 500 GB Hard drive, 2.3 GHz core i5; and one Mac Mini (10.8.2), 4GB Ram, 500 GB Hard drive, 2.3 GHz core i5.

I use both of them to run graphic simulation (using C++/opengl). The big problem is: Mac Mini is about 5 times slower than MacBook. My question is WHY?

Both the computers use the same compiler, same libraries, same code...

I was wondering it may be because of the display: mac mini is hooked up with a VGA monitor. So, I turned off the graphics-heavy part, and just ran the simulation (which produces data files only). Still no luck :(

Also, can the operating system make a difference? I thought the newer the faster.

Any thoughts/suggestions/stupid little tricks?
 
Thanks for the reply, upgrading to 10.8 for the mbp would take some time for me (it's an office laptop, and it will cost some money).

After doing some further tests with my code and the machines (getting rid of graphics part/turning off display/hooking up mbp to a VGA monitor etc), it looks like display is not the problem.

If anybody else has some ideas, please chime in :)

If someone is absolutely sure that 10.8 is causing the problem, let me know and I will downgrade the Mac mini to 10.6.
 
First, the 2011 Mac Mini can't be downgraded to OS X 10.6. Its EFI prevents that.

Second, there are essentially two things that could cause this issue.

First, a bug or something like that in OS X 10.8, which could cause certain programs run slower.

Second, something is wrong in your software. The only thing that helps here is a complete reinstall.

But first, do a benchmark (like geekbench) to see if the hardware of your Mini is as fast as the one in your MacBook. If it's significantly slower, you may have a hardware problem (although I doubt it as everything seems to work).
 
As you're running apps specifically in OpenGL I'd think that the difference in video card is at least part of it. No idea if you're having the same issues with only the calculations aspect though.
 
Thanks for the helpful suggestions, and thanks for pointing out I can't downgrade. I will try the geekbench thing asap.

I did a reinstall of OS X on Mac Mini, and we (in a group) wrote the source code for the software.

Looks like calculations aspects are running slower in Mac Mini: I ran the code taking off the graphics part. I will do some more checks on that though.

p.s. I appreciate the prompt reply really. You guys are as helpful as the unix community :)

edit: I ran the geekbench test: MBP 5997, Mac Mini 5984.

Problem solved: :D
The issue was the MBP uses a different C/C++ compiler than the mini. Once I change to g++ on Mac Mini (export CXX=/usr/bin/pathtog++), it runs as fast as the MBP. I am not completely satisfied with the solution though; I will look into it when I have time.
 
Last edited:
Problem solved: :D
The issue was the MBP uses a different C/C++ compiler than the mini. Once I change to g++ on Mac Mini (export CXX=/usr/bin/pathtog++), it runs as fast as the MBP. I am not completely satisfied with the solution though; I will look into it when I have time.

I never would've guessed that. Interesting stuff, thanks for the update.
 
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