Thank you for purchasing through links and ads on this site.
diglloyd Deal Finder...
Buy other stuff at
Blazing-fast PCIe storage for Mac Pro Tower

Snow Leopard Performance

Last updated 2009-08-26 - Send Feedback
Related: mac OS, OSX

This page assess the performance of popular photography-related applications using Mac OS X Snow Leopard as compared with Mac OS X Leopard.

Memory and drive speed influence performance, so be sure to see the Hardware page. If you want an awesome and reliable Mac Pro setup, contact me for a consultation.


Snow Leopard seems snappier with some of the built-in applications like Safari, Mail, etc.

Most tests on this page are insensitive to disk speed. A few are somewhat sensitive to disk speed; all were run using a 4-drive RAID stripe so as to eliminate disk speed as a factor.

Photoshop CS4

Careful testing with multiple trials revealed that Photoshop CS4 on Snow Leopard is faster than on Leopard, and that booting the 64-bit kernel instead 32-bit kernel adds to that advantage.

B&H Deal ZoneDeals by Brand/Category/Savings
Deals expire in 12 hours unless noted. Certain deals may last longer.
$2699 SAVE $300 = 10.0% Canon 11-24mm f/4 EF L USM in Lenses: DSLR
$3299 SAVE $200 = 5.0% Canon EOS 5D Mark IV DSLR in Cameras: DSLR
$1497 SAVE $500 = 25.0% Nikon D750 DSLR in Cameras: DSLR
$2497 SAVE $500 = 16.0% Nikon D810 DSLR in Cameras: DSLR

Photoshop CS4 — diglloydSpeed1

This benchmark is a pure CPU test; it is designed to run in-memory on any machine with at least 4GB memory, thus testing performance without the influence of disk speed. Multiple trials were made in all cases to rule out any error.

Running Leopard (10.5) takes 3% longer on the test than Snow Leopard/32, and 6% longer than Snow Leopard/64. The surprise here is that booting 64-bit Snow Leopard is faster; after all Photoshop CS4 is a 32-bit program. The difference suggests that the 64-bit Snow Leopard kernel is more efficient in general.

A difference of 6% might not sound like much, but Apple charges $500 more for a 2.93GHz Mac Pro Nehalem over a 2.66GHz model for a 10% speed difference. Think of it like a $300 speed upgrade for $25.


Snow Leopard is faster, 64-bit Snow Leopard faster still

Adobe Lightroom — import 128 CR2 RAW files

This test imports 128 CR2 files (21MP files from Canon 1Ds Mark III).

I tested Lightroom running as a 32-bit application and a 64-bit application. Here is how to make sure Lightroom runs as a 64-bit application. It’s a big deal so make sure you do so.

There is nothing quite as nice as a free speed upgrade! The difference is astonishing, showing the power of running a 64-bit application on a 64-bit Snow Leopard kernel. Red bars (top) are Lightroom/32 and blue bars(bottom) are Lightroom/64.

Top bars are with Lightroom running as a 32-bit application, bottom bars are as a 64-bit application. All you have to do is uncheck the box on Leopard or Snow Leopard to get 64-bit behavior. Lightroom/64-bit on Leopard is 8% slower than Snow Leopard/64-bit.

(Sorry, data label sizes are a bug in Excel, what else is new?!).

Snow Leopard is faster, 64-bit Snow Leopard faster still

Apple Aperture — import 128 CR2 RAW files

This test imports 128 CR2 files (21MP files from Canon 1Ds Mark III). The files are left where they are (not copied into the Aperture library).

I was dumbfounded when I saw the performance differences here. It took 32% longer on Leopard than on 64-bit Snow Leopard. Amazing! And note that 32-bit Snow Leopard takes 5% longer than 64-bit.

Awesome performance using Snow Leopard!

Canon Digital Photo Professional —
Process 128 CR2 RAW files to 16-bit TIF

This test processes 128 CR2 files (21MP files from Canon 1Ds Mark III) to 16-bit uncompressed TIF.

Mac OS X Leopard and Snow Leopard/32-bit take 5.8% longer to get the job done than Snow Leopard/64-bit.

64-bit Snow Leopard faster, 32-bit the same as Leopard

Nikon Capture NX2 2.2.0 —
Process 16 D3x NEFs to 16-bit TIF

Note that this test is with version 2.2.0; version 2.2.2 is completely non-functional with NEF.

The gain here is tremendous: 20% gain in 64-bit mode over Leopard. A good thing too, since NX2 is pathetically slow, that’s why only 16 files were processed for this test.

Wow! 20% gain in 64-bit mode over Leopard!


Helicon Focus

This test focus-stacks nine 16-bit 21-megapixel images. Helicon Focus 4.1.1 is a 64-bit application (one of the few), so some of the gains might be due to matching a 64-bit kernel to a 64-bit application.

I had such a hard time believing these results that I re-ran them all. No change, the results were consistent.

Wow! Look at the speed difference between Leopard and Snow Leopard 64-bit: 18%! That’s as if a 2.66GHz machine were suddenly running at 3.1GHz! I’ve simply never seen that kind of change with an operating system update ever before.

Wow!!! An 18% gain with 64-bit-kernel Snow Leopard!



Click to order at OWC

Snow Leopard booted into the 32-bit kernel is always faster than Leopard, with fair to substantial gains, depending on the application.

But Snow Leopard booted into the 64-bit kernel shows a consistent performance advantage over Leopard, and even more advantage over 32-bit Snow Leopard as well. Performance gains of up to 30% were observed, making Snow Leopard by far the best value for the money in a long, long time. At about $25 , you won’t find a more compelling upgrade of any kind, anywhere.

Apple’s decision to default Snow Leopard into 32-bit-kernel mode is a losing proposition for most photography related applications: boot into 64-bit mode if you don’t have any hardware/software that precludes it. See the software and hardware compatibility pages. Remember too that you can reboot to switch between 32-bit and 64-bit mode should you have programs or hardware that you need only sporadically.


ThunderBay 4 - The Speed To Create. The Capacity To Dream.
Storage Wishlist… | Terms of Use | PRIVACY POLICY
Contact | About Lloyd Chambers | Consulting | Photo Tours
Mailing Lists | RSS Feeds | Twitter
Copyright © 2008-2017 diglloyd Inc, all rights reserved.
Display info: __RETINA_INFO_STATUS__