Aperture an the new 2013 Mac Pro

Hi folks,

I have not been on the board for a long time, I was just interested to read what the community was doing with the new Mac Pro. However, after seeing this article I had to say something, and for those who know me, it is always rather long-winded, but hopefully helpful.

I just read that Macworld article and found it to be INCREDIBLY inaccurate, most especially the part about RAM. As an engineer and programmer for 40 years, this kind of published misinformation makes me furious because it costs trusting users time and money chasing the wrong things. That was 100% wrong, and it is easy to prove this and see the reality for yourself. This way informed decisions about how a computer handles the work you are actually doing are easily made, with very small amounts of actual technical knowledge, and a couple of software tools that Apple provides on all systems for free: Activity Monitor and Terminal.

Trust me the #1 thing Aperture needs for maximum performance is RAM, and you all have the utility software on your Macs to prove this to yourself, no conjecture, no guessing, you can see it happening in real time. This free app is called Activity Monitor, and it is in your Utilities folder. With this tool you can easily see the RAM use of all apps and processes in your system, and you will see as you work on Aperture that it has a big desire for free system RAM.

First of all, let me make a blanket statement that all OS X machines will increase performance with more RAM is going to be true until you get to the VERY high end of RAM usage, over say 96GB RAM, and that is only possible in the Mac Pro in special cases. SOOOO...that means that every other Mac that is not a Mac Pro will only deliver its maximum possible performance with the maximum amount of RAM the system allows.

Why am a saying this with 100% certainty? Simple...stay with me here... to understand this fully, I need to introduce 2 UNIX terms, pageins and pageouts. I will show you where your Mac displays these figures, and as part of the very old school architecture of UNIX, these two numbers are kept by your system continuously, and only reset to zero when you restart your Mac. A pageout is when the operating system runs out of RAM for a current task, and the UNIX OS writes the current contents of a chunk of RAM to a tempoary "page" on disk to free up that RAM space. When the app needs that data it pagedout again, it will have to re-read that data from the pageout file on disk back into ram or "pagein" before it can use it again. Obviously, read/write access to RAM is orders of magnatude faster than disk access, even if that disk is an SSD. You can only avoid paging if your system always has sufficient free RAM for your apps to work with, and therefore never has to page or swap data from RAM to disk and back again.

Therefore, UNIX RAM usage methodology dictates if you can keep RAM pageouts to a mimimum. ideally zero, your CPUs are processing at maximum speed, limited only by I/O. Paged storage is also called virtual memory or VM by the UNIX system.

OK, fair enough, then do you have enough RAM to avoid this slowdown of paging memory? Simple to answer....open your Terminal app. When it opens, type the word top and hit Return. A verbose screen full of techincal items will appear, and the 6th line down shows status of Virtual Memory, labeled VM:. At the end of that line will be figures for number of pageins and pageouts. If your Pageouts are zero, congratulations your Mac is operating 100% in RAM (at least since your last reboot, as Pagein and pageout is reset at each system restart). Most likely, your Pageout count is a very large number. I now suggest restarting your Mac, when it reboots open Terminal again, type top and check the Pageout value to now be zero, then run Aperture for a while and type top and check the Pageouts again. Given my own systems, after using Aperture for an hour or so of regular array of tasks, I will see some Pageouts unless I am using one of the systems over 48GB. Then, I will see them if I am working with some of my medium format files or large film scans. The dead giveaway for a pageout is the beachball, btw...unless you are doing something else in the background, when you see a beachball in Aperture it is paging.

To see more details on actual RAM usage, I suggest you open Activity Monitor and keep it visible and look at the free RAM as you work with Aperture. Remember, being a UNIX system, the key performance element in all applications is avoiding pageouts.

From reading a lot of the questions here about the new Mac Pro configs, I figure I should write up my conclusions on where I stand with current configs.

I have to sign off now but I will tell you the sweet spot config for my work is 6 core, 64GB RAM (buy 12GB from Apple, buy the RAM from Datamem or OWC), 1TB storage. The GPU selection requires discussion to understand, but the cost difference between D300 and D500 is very small, and the 500 is Tahiti-based.

More to come later in the week, hope this helps.

KJ Doyle