Re: SSD TRIM / "discard" works after a remount with mount -a?

[Benny Siegert <bsiegert%gmail.com@localhost>]

> I have a scenario where I have several NetBSD systems which were just upgraded to SSDs. I forgot to turn on discard (TRIM) support on the drives when I first put them in. 

I don’t think that’s a big deal. For the record, I have run my SSD without TRIM on NetBSD for a long while now. In fact, your email taught me about the „discard“ option :¬


> 1. Edit /etc/fstab, and add the "discard" option to all FFS file systems

OK.

> 2. Run "mount -a" which should re-mount the affected file systems  with
>   the newly added option. I'm assuming this work for the trim/discard
>   opton.

Reboot?

Otherwise, to enable TRIM without rebooting, try:

mount -uo discard /

> 3. dd if=/dev/zero bs=4096k of=/my/affected/file/system/DELETEME.000
>   I'm assuming short blocks get written as partials.

I would skip this step and the following ones. They likely do more harm than good.

—Benny.