Leonidas Spyropoulos posted on Fri, 24 May 2013 23:38:17 +0100 as excerpted:
> On 24 May 2013 21:07, "cwillu" <cwi...@cwillu.com> wrote: >> >> No need to specify ssd, it's automatically detected. > I'm not so sure it did detected. When I manually set it I saw > significant improvement. Without going back to check the wiki, IIRC it was there that the /sys paths it checks for that detection are listed. Those paths are then based on what the drive itself claims. If it claims to be rotating storage... It may also depend on the kernel version, etc, as I'm not sure when that auto-detection was added (tho for all I know it has been there awhile). I do know my new SSDs (Corsair Neutrons, 256GB) are detected here, and the ssd mount option is thus not needed. However, I'm running current v3.10-rcX-git kernels, tho I'm a few days behind ATM as I'm still working on switching over to the SSDs ATM and am having to do some reconfiguring to get there. Btrfs still being marked for testing only and under heavy development, if people aren't at least running current Linus stable or better and don't have a specific bug as a reason not to, they're actually behind and are likely missing potentially critical patches. That means most people trying to run btrfs on stock distro kernels will be behind... Meanwhile, what about the discard option? As I'm still setting up on the SSDs as well as btrfs here, I haven't had a chance to decide whether I want that, or would rather setup fstrim as a cron job, or what. But that's the other big question for SSD. Here, I'm actually partitioning for near 100% over-provisioning, (120-ish GiB of partitions on the 238GiB/256GB drives, so I suspect actually running with discard as a mount option won't be such a big deal and will likely only cut write performance as I head toward stable-state, since the drive should have plenty of trimmed space to work with in any case due to the over-provisioning. But I suspect it could be of benefit to those much closer to 0% over-provisioning than to my near 100%. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- 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
