On Sep 25, 2013, at 9:02 AM, Michael Cronenworth <mike(a)cchtml.com> wrote:
Chris Murphy wrote:
> So as it turns out some devices get really busy and slow down when TRIM is used, so
not all devices are well suited for discard and therefore it's probably not a good
idea for it to be set by default. It's also not enabled by default for ssds with btrfs
either. And with dm-crypt there's a security concern in that it exposes massive
zero'd holes on the device instead of current data being obscured by stale data.
[citation needed]
https://patrick-nagel.net/blog/archives/337
https://btrfs.wiki.kernel.org/index.php/FAQ#Does_Btrfs_support_TRIM.2Fdis...
I have 4 SSDs of various manufacturers all used as root and boot drives. All use ext4 and
have TRIM enabled. I have yet to experience any perceived slow downs.
OK but is that ext4 on the physical device or is LVM or RAID in between? I don't think
TRIM passthrough to the physical device is default behavior with either LVM or md. If ext4
is directly on the physical device, all this says is you have four SSD models that
aren't negatively impacted by TRIM. There are hundreds of models of SSDs.
Chris Murphy