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In any computer, there is a bottleneck. The processor, the amount of memory, the bus to the hard drive, etc.

I just ordered a 2010 MacPro, 12 core, and although the 12*3.33 GHz cores should give me more than 3x the performance of my quad 2.8 GHz, I understand it probably won't. I am wondering what the weak link will be and how to improve it. The first thing I'm considering is a PCI card with 2 SSD RAID 0 to run the OS. On my old Pro, I saw amazing boot times from a shift to SSD. The Mac will have 32GB of RAM, I'm assuming that's enough.

Update - One example of an intensive process is video encoding. How do I find whether writing to the hard drives is the slowdown, i.e. that raid 0 for the hard drives would help the speed?

Any other advice? How do I identify the bottlenecks once this machine is running?

  • Are you looking for Activity Monitor? – bmike Nov 12 '15 at 12:18
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The "biggest" bottleneck will be the I/O, as that is the slowest bus on the system (in comparison with the CPU and memory buses).

Because you're willing to use PCIe, even the 2.0 version that's on the MacPro from that era, you should be able to get closer to the SATA 3 speeds (6Gb/s) of modern SSD's (afaik, the onboard SATA bus is SATA II -- 3 Gb/s).

Your best bet for looking at bottlenecks is taking a look at the specifications (I believe there is a 3.3Ghz CPU with matching memory speeds that will also give you a little less bottleneckage).

  • Sound advice. You can also get the dual 6's in 3.46GHz. I have one. – Tetsujin Nov 12 '15 at 14:25
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OP I think you're looking at the problem a little backwards. Your weakest link will inherently be the I/O bus. That being said, raid-0 on PCI-e SSDs will be quite performant.

You need to ask yourself a couple questions

  • What are you trying to optimize for? Its a mac pro and you're cosnidering a significant $ investment, so you're probably doing some professional work. Keep in mind though that you're sinking a lot of money into a 5+ year old machine, and the parts won't be reusable on any new mac pro you buy in the future

  • What are your pain points now? You just ordered this machine, so you haven't actually used it yet as part of your workflow. Firstly, you might find it more than adequate for what you want to do. But currently, what are the things you are struggling with? We can help answer from there.

  • +1, I appreciate the answer. In my question, I guess I assume that everything isn't perfectly balanced, that there are changes that might improve bottleneck. If my 4 core Pro now runs showing 8 threads all redlined on a process, I'd assume the bus isn't the issue, but on new 12 core, if cores aren't all maxed, then it's the bus or HD access that's holding up the cores. (The new 12core Pro was $1700. Not really expensive compared to $8K it sold new) – JTP - Apologise to Monica Nov 18 '15 at 18:33
  • That's something you'll need to test once you have the new rig set up. if you see that 24 threads aren't maxed out, then you'll know the bottleneck is elsewhere - OR there is just sufficient performance on all counts. How big are the files you're generating? if you have sufficient ram, then it could just be writing to filesystem cache regardless of drive speed, and swapping it out later. – Vitalydotn Nov 18 '15 at 19:32
  • Yes, thanks again. Machine comes tomorrow, so I'll be testing over the weekend to optimize. Video files of 2 hours transcoding to go from DV to MP4 is the most intensive thing. – JTP - Apologise to Monica Nov 18 '15 at 19:46
  • I'm interested to hear your results, and we can take it from there! One thing about Raid-0: if you lose one disk, you've lost everything. Make sure you have great backups, or I would reconsider Raid-0. – Vitalydotn Nov 18 '15 at 20:02

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