I can't seem to find an answer to this so I thought I would ask here:
/etc/fstab and when using the mount command in ext4 you would add the option
discard to activate TRIM on an SSD. Similarly the
discard option activates TRIM on btrfs volumes as confirmed at btrfs.wiki.kernel.org.
Btrfs is supposed to enable copy on write by nature and if this is the case does the discard option effectively disable copy on write?
I'm imagining TRIM erasing all of the blocks that would have contained previous versions of files. If copy on write still functions doesn't that reduce the performance of an SSD long term, if eventually none of the blocks are zeroed out?