With Speedmark 7 development behind us, Macworld Lab can once again focus on other Mac-related performance stories. On the top of the list of projects is a follow-up on previous Thunderbolt performance stories (Thunderbolt versus FireWire and USB 2.0, Target Disk Mode and more). This time around, we look at Lion versus Snow Leopard performance, MacBook Air performance, and update our eSATA comparison results using a 6Gbps ExpressCard from StarTech.

In our testing, we used the Thunderbolt-equipped Promise Pegasus R6. We also used a Promise SmartStor DS4600. (We don't have access to a non-Thunderbolt to an array that's similar to the R6.)

Snow Leopard versus Lion

Our first few lab reports on Thunderbolt were done before Lion was released. Now that Lion has been released upon the Mac world, we ran tests to see if the operating system affects performance. We tested a Thunderbolt-equipped 17-inch MacBook Pro with a 256GB SSD with Snow Leopard and then with Lion.

Performance wasn't affected much by the new operating system. Each of our six tasks were a megabyte or two per second slower under Lion when testing eSATA speeds. Results were mixed on the Thunderbolt tests, though, with half of the tests (AJA System Test read, 2GB file read and write) speeding up under Lion and the half of the test slowing down a bit.

Overall, I'd say its a wash, with the average Thunderbolt file transfer speeds being less than one percent slower on Lion than on Snow Leopard, while AJA Read tests were 7 percent faster on Lion and AJA Write tests were 9 percent faster on Snow Leopard.

MacBook Air vs. 17-inch MacBook Pro

It hardly seems fair pitting the diminutive MacBook Air up against Apple's largest laptop, but it turns out that the speedy flash storage in the Air helped it take top honors in three of the six tests. The average file and folder transfer speeds were almost identical between the two, as was the AJA System Test Read scores. The AJA write tests were 6 percent faster on the Air.

eSATA 6Gbps vs. Thunderbolt

We received a 2-port 6Gbps ExpressCard eSATA Controller Card from StarTech and tested it with our 17-inch MacBook Pro and the Promise SmartStor SD4600. Compared to the results of a 3Gbps Apricorn eSATA ExpressCard, the Promise SmartStor DS4600 using the 6Gbps card was nearly twice as fast in the AJA System Test read scores and 33 percent faster in the AJA write test. In our files and folders transfer tests, the 6Gbps card was 44 percent faster reading a 2GB file, 30 percent faster reading a 2GB folder, 34 percent faster writing a 2GB file and 24 percent faster reading a 2GB folder.

These faster speeds also closed the performance gap between eSATA and Thunderbolt, though many tests were still much faster with Thunderbolt. For example, Thunderbolt was still 2.5 times faster reading and 5.5 times faster writing than eSATA 6Gbps in our AJA System Test. In our files and folders transfer tests, writing is still considerably faster on Thunderbolt, with 74 percent faster file writing and 59 percent folder writing times. Our read speed results were much closer with the Thunderbolt drive being a little more than 2 percent faster than eSATA in our file transfer and eSATA actually finishing the folder read test nearly 4 percent faster than Thunderbolt.

The drives we tested with are not identical, but they're as close as we can get with the hardware we have on hand.