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I have a SSD OCZ Vertex4 installed on my laptop. I'm running Ubuntu 12.04 LTS. I have enable TRIM by adding "discard" to my fstab file. (also added option noatime). I rebooted my Ubuntu and followed These instructions here to test TRIM. The end results of my tempfile was all ffff's, when it should have read all zero's, which is telling me TRIM is not really working or enabled correctly.

Did I miss something?

Also, will it be a problem if only my /home directory is encrypted.

AND if you ask why I have swap on my SSD, it's because I let Ubuntu set up my partition. When I have my SSD, I just wanted to install Ubuntu as fast as possible. =) I've done testing to see at which point it will start to use swap and it took a lot of applications open to finally use swap. I currently have 4 GB of memory. I might shrink this to like 512 MB or 1 GB the most.

Here's some info about my file system setup.

sudo hdparm -I /dev/sda1 | grep "TRIM supported" 

Data Set Management TRIM supported (limit 16 blocks) 

sudo fdisk -l /dev/sda

Device Boot      Start         End      Blocks   Id  System 
/dev/sda1   *        2048   242016255   121007104   83  Linux 
/dev/sda2       242018302   250068991     4025345    5  Extended 
/dev/sda5       242018304   250068991     4025344   82  Linux swap / Solaris 

ls /dev/mapper

control  cryptswap1
share|improve this question
Did you see @dimmer's comment under the answer you linked to? It goes to this related answer, which might be helpful. Also, I'm using a SSD with 8GB of RAM and no swap or TRIM. It's not everyone's preferred setup but I've never hit more than 3GB RAM usage (except when using VirtualBox), and I'm not concerned about wearing out the SSD. – Tom Brossman Aug 28 '12 at 8:52
@TomBrossman i totally missed that. Was a little helpful. but still unsure of whether or not its actually working. At least my dmesg in /var/log does not state any "discard not supported, disabling". So "seems" like it's working. Thanks for the reply – M_M Aug 28 '12 at 15:25

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