[stoppingdown]

23.5Mbyte/sec would be quite poor for an SSD...   (even for an HDD) . All my figures were in bytes/sec. The PCIe SSD in the Retina MacBook Pros really reads at 1.6Gbytes/sec and writes at 1.0Gbytes/sec (confirmed by a quick-n-dirty test). In other words, they can read the dump of a DVD in a matter of seconds.

 

Also for me is partially obscure what use LR makes of the graphic card (it does, also because there's an option to deactivate it). For sure there's a visible effect when you touch the editing sliders. I'm unsure on whether it also uses it for operations such as batch processing.

 

PS Measured on an encrypted partition. On the newest MBP it's unclear to me where the bottleneck is, but since the CPU has hardware acceleration for AES encryption, and benchmarks in RAM show a speed of 4/5 GBytes per second, I presume encryption - at least the one provided by HFS+ - doesn't impact speed.

Code:

[Mistral:~] fritz% dd if=/dev/zero of=test bs=1024k count=10240
10240+0 records in
10240+0 records out
10737418240 bytes transferred in 11.366524 secs (944652759 bytes/sec)
[Mistral:~] fritz% sudo purge (clears RAM cache)
Password:
[Mistral:~] fritz% dd of=/dev/null if=test bs=1024k count=10240
10240+0 records in
10240+0 records out
10737418240 bytes transferred in 5.854027 secs (1834193484 bytes/sec)