To see the details for your weekly cron jobs, change directory to /etc/cron.weekly or include it in the command as below:
more /etc/cron.weekly/fstrim
You should see an output which looks something like:
#!/bin/sh
# trim all mounted file systems which support it
/sbin/fstrim --all || true
If this is present trim is active/checked and executed once a week. The help on this command will show you...
fstrim --help
Usage:
fstrim [options] <mount point>
Options:
-a, --all trim all mounted filesystems that are supported
-o, --offset <num> the offset in bytes to start discarding from
-l, --length <num> the number of bytes to discard
-m, --minimum <num> the minimum extent length to discard
-v, --verbose print number of discarded bytes
-h, --help display this help and exit
-V, --version output version information and exit
To see if trim is supported (change sda if you have more than 1 disks):
sudo hdparm -I /dev/sda | grep "TRIM supported"
and it should show something similar to this:
* Data Set Management TRIM supported (limit 8 blocks)
