Have dual Samsung 840 Pros on Sonnet Tempo Pro card, installed in 12-core MacPro 5,1, RAID0. Running 10.9.2. Everything is sweet. Single question, enable TRIM on 840s? If yes, which one?
Even if you do not use TRIM directly, all modern SSD's have internal garbage collection (IGC) that does the same thing, albeit at a much slower pace.
TRIM is nice because it can do it all in one fell swoop because the OS knows when the computer is idle and can call a request for TRIM from the SSD controller. But because the controller doesn't know when the computer is idle it does IGC very sporadically as not to affect user experience.
This is how SSD's were able to function ok over time in RAID 0 before RAID controllers could pass TRIM commands. The 2 drives just healed themselves over time.
Not quite. The GC doesn't know if a chunk of data that the disk thinks is in use is actually in use by the OS. TRIM let's the OS say that "these chunks are free, go ahead and erase them during GC".
Without TRIM, the disk often has to preserve (copy) data that the OS has deleted - since it has no way of knowing that the file system no longer references the blocks on disk.
"Healed" is an interesting term for an operation that contributes to the drive wearing out, but does improve performance in the short term.