Jason Discount:
My personal take from the numbers is that Lion FileVault comes at a large performance hit on Core 2 Duo machines w/Toshiba drives; a performance hit that I would personally find unacceptable. Inversely, the performance hit on a Core i7 machine w/Samsung drive is 3x less drastic, and thus, for me, well worth it.
Another way of looking at it is that the encrypted, slower SSD on the slower MacBook Air is still way faster than any notebook hard drive.
Matt Neuburg:
On the other hand, the fact is that when Lion caused Preview to quit automatically yesterday on my machine, I was using Preview. I wasn’t using it actively at that moment in a way that Lion knew about — there were no open Preview windows, and Preview wasn’t frontmost — but I was engaged in some activity involving Preview. I had switched away from Preview only in order to prepare things in the Finder so that the document I intended to open in Preview would be ready. But when I switched back to Preview with Command-Tab, Preview was gone. That’s not helpful or useful; it’s annoying, confusing, and a hindrance. I had to launch Preview explicitly again in order to continue with my task.
I’ve seen the same issue with Preview, QuickTime Player, and TextEdit. Since I don’t use Command-Tab, it doesn’t really bother me except for the constant appearing and disappearing from the Dock. If there’s no memory pressure, the system should wait a while in case you’re going to switch right back to the same application.
