Linux apps on x86 Macs? Please help

[DarkPrime]

I originally posted this in the software forum, but feel it should have been here instead:

I'm helping my boss select 3 new "super workstations" to be used by myself and a couple others. We are looking to get dual-quad-core xeons to work with. We want all the power we can get today for two reasons: future-proof (well for a little while) and we actually can and will use the power of these machines. This brings me to why I need a little help. Our high-performance computing codes are set to run within linux. We are also using things like MPI2 and UPC for some of our models. The thing is, my boss really loves the new dual 3.0ghz quad core xeons (and a quadro 4500 fx) from Apple. I have configured a machine for about 10k and it's a monster of a beast. I've gotten an almost as capable dell for 9k configured (2.66 ghz chips and quadro 3500 fx). If we got the dells, we would probably be running Suse 10.2 at the moment on them, and I know our codes would be fine. Are there any issues compiling and running these issues within the Mac OS? Are there special things I need to know about the shell or terminal window mac uses? Is there a big difference with the file system on the mac from most linux distros? I just need to know what things we need to watch out for if we leave our current dells to go to these new macs. Any help is so very much appreciated. Thanks!

 

[n0cmonkey]

There may be issues, but unless you're using custom kernel modules they shouldn't be anything that can't be worked around.

Get a mini and give it a shot.

 

[DarkPrime]

That wouldn't be a bad idea, but we don't have time to buy one, wait, and then run the risk of losing our budget to buy these 3 beasts.

 

[n0cmonkey]

If you don't have the time to do proper testing, you don't want to get a major unknown.

 

[DarkPrime]

Hey, I totally understand that, but i'm not the one who gets to make the final decisions.

 

[sourceninja]

If your boss likes the hardware, just run linux on them. Linux runs on apple hardware.

 

[Nothinman]

Are there any issues compiling and running these issues within the Mac OS?

Probably since they're not the same OS at all.

Are there special things I need to know about the shell or terminal window mac uses?

I believe Apple finally caught up to modern systems and started using bash so that should be about the same.

Is there a big difference with the file system on the mac from most linux distros?

I don't remember what kind of generic unix compatibility directories/symlinks there are but the layout and on-data format of the filesystems (OS X uses HFS and you're probably using ext3 on Linux but I doubt you're going that deep or you'd know already) are very different.

I just need to know what things we need to watch out for if we leave our current dells to go to these new macs.

You're completely switching OSes so you'd have to do a lot of testing and likely fixing to make sure your code runs right on the new system.

If your boss likes the hardware, just run linux on them. Linux runs on apple hardware.

True but it's not 100% because of Apple's use of EFI. Using BootCamp might make it simpler, especially if you leave OS X on there dualboot as well, but I'm not sure since I don't own any Macs.

 

[SoundTheSurrender]

Maybe this will help?

KDE4 running in OSX

http://forum.insanelymac.com/index.php?showtopic=42845

 

[drag]

No it won't help, not unless your application dependancies include QT libraries.

If you are curious realy then N0cmonkey's suggestion is the best. Run down to the store and get a Mac mini and start compiling away. If your lucky your using minimal dependancies on GNU software that generally has been ported over to OS X and it shouldn't go so bad.

If your unlucky your software requires propriatory software that is unaviable for the Mac platform and/or uses extensive amounts of third party dependancies that won't run on OS X without significant modifications.

(btw Linux's performance is generally better then OS X by a decent enough margin so that it matters....)

 

[tatteredpotato]

Mac hardware is popular enough you should be able to find linux compatibility online somewhere.

 

[drag]

Oh and you asked about file systems..

The default HFS+ is non-POSIX compatable. Most things work, some things won't. In addition it's not case sensitive. It uses BSD VFS to emulate a Unix file system, but underneath it's very different.

OS X provides support for UFS, which is what you'll need for maximum compatability.


and ya you can run Linux on Apple hardware for the most part. I've done that quite a bit myself.

 

[Nothinman]

Mac hardware is popular enough you should be able to find linux compatibility online somewhere.

Current Mac hardware is generic PC hardware with EFI slapped on, there's nothing special about it besides the branding and the jacked up price.

 

[DarkPrime]

Thank you to everyone for your inputs. I knew Mac OS was based on BSD, but also knew that there are some major differences between it and a traditional Unix/Linux environment.

The codes and models we are using use as much open source material as possible and all can compile with the GNU compilers in linux.

Another thing I don't know about is how effeciently does OS X handle multiple jobs? The machines being purchased will have 8 cores (dual quad cores) and I wonder how will the OS's ability of load balancing compare to say SUSE 10.2? Does anyone have any input on that issue for me? Thanks.

 

[sourceninja]

Originally posted by: Nothinman

If your boss likes the hardware, just run linux on them. Linux runs on apple hardware.

True but it's not 100% because of Apple's use of EFI. Using BootCamp might make it simpler, especially if you leave OS X on there dualboot as well, but I'm not sure since I don't own any Macs.

There are extensions to EFI that can help and I think there is a ELILO and rEFIt, those are the two tools you need and they get the job done.

 

[drag]

Anandtech did some comparisions between Linux and OS X a while back.

It compared multi-threaded MySQL performance. OS X got trounced very badly. Although this could be very likely due to the very Linux-oriented nature of Mysql.

Going from 1 thread to 50 threads on dual G5 took OS X's performance from 100% to 25%

While similarly on Linux going from 1 thread to 50 threads on the same (or at least very similar) machine went from 100% to 182% (and better for Opterons)

Explaination is:
http://www.anandtech.com/mac/showdoc.aspx?i=2520&p=8

MySQL had similar problems on FreeBSD until they started using linux-threads (2.4 Linux style threading library) for it.

This guy originally did benchmarks that made OS X look VERY bad compared to Linux then compared to XP with Linux winning.

In that link he re-did the tests after getting a lot of feeback from Apple and other people and used optimized code that provided improvements for all systems, but especially OS X.

Then using a third party memory allocation library they were able to get OS X's performance very close to Linux's performance.

That was a while ago, so I expect that OS X has gotten better and closed lot of the gap.


For comparision sake maybe check out penguin computing and see what sort of things they offer and how the price compares. They have a few quad core things.

If you want to aim for high-density CPU power you realy can't beat blade servers...

 

[Nothinman]

There are extensions to EFI that can help and I think there is a ELILO and rEFIt, those are the two tools you need and they get the job done.

The extensions are part of BootCamp but you'll need to use OS X to install them AFAIK and it would probably be a good idea to leave OS X there if you go that route so that's a big waste of disk space. I haven't directly used ELILO or rEFIt but the discussions I saw about them made them seem pretty immature so far so it's hard to say how much work it would be to get that all going.