TRIM Question [SOLVED]

[crboone]

I've been researching how to trim my SSD boot drive but am having problems making it work. First, TRIM does seem to be supported for my drive, per:

HP-Pavilion-Mini / # hdparm -I /dev/sdb | grep TRIM
* Data Set Management TRIM supported (limit 1 block)
* Deterministic read data after TRIM


But for some reason, I cannot seem to run fstrim:

HP-Pavilion-Mini / # sudo -v fstrim /
usage: sudo -h | -K | -k | -V
usage: sudo -v [-AknS] [-g group] [-h host] [-p prompt] [-u user]
usage: sudo -l [-AknS] [-g group] [-h host] [-p prompt] [-U user] [-u user] [command]
usage: sudo [-AbEHknPS] [-r role] [-t type] [-C num] [-g group] [-h host] [-p prompt] [-u user]
[VAR=value] [-i|-s] [<command>]
usage: sudo -e [-AknS] [-r role] [-t type] [-C num] [-g group] [-h host] [-p prompt] [-u user] file ...


** Could someone tell me what the correct command is for this now?


Also, if I were to add this to fstab, would I simply add "discard" to the following line (before the errors...)?

UUID=2319eb2f-9eab-454c-85a4-1dd7990bf8b1 / ext4 errors=remount-ro 0 1

or should I change it to:

UUID=[UUID of SSD mount] / ext4 defaults,noatime,discard 0 1


Thanks for any help.

[Mute Ant]

Because it's COMMAND OPTIONS ARGUMENTS
Your -v option got applied to the sudo command. Try...

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sudo  fstrim  -v  /

...or if you are already root, miss out the sudo.

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fstrim -v /

/etc/fstab entries go...

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WHAT   WHERE   TYPE   O,P,T,I,O,N,S   0   1

...so...

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UUID=2319eb2f-9eab-454c-85a4-1dd7990bf8b1   /   ext4   discard,errors=remount-ro   0   1

...and...

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UUID=2319eb2f-9eab-454c-85a4-1dd7990bf8b1   /   ext4   errors=remount-ro,discard   0   1

...have exactly the same effect. You might like to add noatime to stop every read causing a write...

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UUID=2319eb2f-9eab-454c-85a4-1dd7990bf8b1   /   ext4   errors=remount-ro,discard,noatime   0   1

[crboone]

Yes, thank you -- I think the page that I got the command from just had a typo (it mistakenly had the -v first so I did a copy/paste of that command). Unfortunately, it doesn't work the other way either:

# sudo fstrim -v /
fstrim: /: FITRIM ioctl failed: Operation not supported

As root:

# fstrim -v /
fstrim: /: FITRIM ioctl failed: Operation not supported

Why would the hdparm indicate TRIM is supported but the fstrim operation is not supported?

I may just add the fstab options -- but I had read that wasn't as good to use (not sure why though).

[Mute Ant]

''Why would the hdparm indicate TRIM is supported but the fstrim operation is not supported?'' My guess is that ''running on an external SSD'' stops 'trim' commands getting to the drive.

[crboone]

Even though the OS is running on the drive? I suppose there must be some difference, I guess.

[Mute Ant]

''the OS is running on the drive?'' No, copied from the drive into RAM.

[crboone]

I found this link that supports your answer (thought it's a bit dated):

http://askubuntu.com/questions/262154/t ... -supported

I suppose this is one reason to purchase an internal SSD before too long.

[crboone]

I've installed the SSD internally and the fstrim operation does appear to be working.