On Sun, 2012-02-12 at 16:14 -0800, Marc MERLIN wrote: > Considering that I have a fairly new crucial 256GB SDD, I'm going to assume > that this bit applies to me: > "On the other side, TRIM is usually overrated. Drive itself should keep good > performance even without TRIM, either by using internal garbage collecting > process or by some area reserved for optimal writes handling." > > So it sounds like I should just not give the "ssd" mount option to btrfs, > and not worry about TRIM.
The 'ssd' option on btrfs is actually completely unrelated to trim support. Instead, it changes how blocks are allocated on the device, taking advantage of the the improved random read/write speed. The 'ssd' option should be autodetected on most SSDs, but I don't know if this is handled correctly when you're using dm-crypt. (Btrfs prints a message at mount time when it autodetects this.) It shouldn't hurt to leave it. Discard is handled with a separate mount option on btrfs (called 'discard'), and is disabled by default even if you have the 'ssd' option enabled, because of the negative performance impact it has had on some SSDs. -- Calvin Walton <calvin.wal...@kepstin.ca> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
