Dear all,
Having just upgraded my Mac Pro from 16GB to 32GB, I did a bit of comparison in order to figure out to what extend I had wasted 970 US$.
It turns out that on my typical heavily parallelized usage, there is some value, but not all applications show the same level of gains:
PS CS4: important gains with 10 mins saving on a simple scenario on a large image
PTgui: 20 mins saving on the computation of a large panorama
C1 Pro: no gains
Autopano Pro: no gains
Details
Test conditions
Hardware
first gen 8 core Mac Pro (667 Mz) 3.0 Ghz
Test 1: 8x2GB = 16GB RAM
Test 2: 8x4GB = 32GB RAM
OS: OS 10.5.6
Internal storage
Boot disk: Velociraptor 300GB
Scratch 1 (APP): single 150GB raptor
Scratch 2 (PS and PTgui): softraid controlled Raid 0 volume with 2x150GB Raptor
External storage
Wiebetech RTX600 with 6x1TB Seagate in Raid 5 mode and SCSI320 interface
Key imaging applications
PS CS4
C1 4.6.2
PTgui Pro 8.1
Autopano Pro 1.42
Background applications
Bridge CS4
Safari 4 beta
iTune 7.6
Activity Monitor
Scenario preparation
Boot OSX
Launch all applications
Point to the right folders
Scenario (all files read and written from Wiebetech SCSI unit) – all tasks launched at about the same time
PS CS4: Open from bridge CS4 a 3.5GB .psb file and then flatten the layers in the file
C1: export of 213 D3X raw files to jpg
PTgui: batch compute a 150 megapixel pano
APP: launch an interactive computation of a 150 megapixel HDR pano
The scenario was played once with 16GB RAM and once with 32GB RAM.
Test results
Time
PS CS4
- 16GB RAM:
Open: 4:30 min
Flatten layers: 15 min
Total: 19:30 min
- 32GB RAM:
Open: 5:40 min
Flatten layers: 5:30 min
Total: 11:10 min
C1
16 GB RAM: 32 min
32 GB RAM: 32 min
PTgui
16 GB RAM: 59 min
32 GB RAM: 40 min
APP
16 GB RAM: 90 min
32 GB RAM: 89 min
Memory usage
16GB
- VM size: 58GB
- Peak active memory usage: 10GB
- Used memory: 15.8/16 GB
32GB
- VM size: 58GB
- Peak active memory usage: 21GB
- Used memory: 31.5/32 GB