On Tue, 20 Apr 2010, Marco Peereboom wrote:
What problem are you trying to solve?
And no, TRIM isn't supported.
My concern is the procedure we've been using to deploy OpenBSD machines.
We set up a base machine with a standard disk layout, utilities, admin
account, etc... and then make a copy of the entire disk using dd. We save
this on our SAN, and when we want a new machine, simply pull a disk off
the shelf, copy the image to the disk, boot, then customize.
The problem is that we're copying the entire disk, so, as far as the disk
(i.e., SSDs) is aware, that disk is 100% full-- all blocks are marked as
used even if they're empty. If I understand correctly, how the controller
handles block reallocation in this scenario depends how it is implemented
in the disk's firmware, with some being better than others. At present,
we have Intel X25-E disks.
So, if the above is correct, then I will need to either rethink our
deployment strategy (like, always leave some spae on the disk, untouched
by dd), or else try not to write so often (like, using a ramdisk). I
could also be overestimating the importance of all of this.
Thanks,
Dan