XFS and trim

[Steven Haigh]

On 04/02/2013 12:19 AM, Josef Bacik wrote:
> On Sat, Mar 30, 2013 at 9:38 PM, Steven Haigh <netwiz at crc.id.au> wrote:
>> Hi all,
>>
>> Firstly, Please CC me into replies as I'm not subscribed to this list.
>>
>> I'm trying to confirm that Fedora 18 has enabled trim for XFS filesystems. I
>> have added discard to the mount options in /etc/fstab - however I do not see
>> it when looking at the output of 'mount':
>>
>> UUID=b95a7b45-d197-45c0-a7d6-c13f930a38b3 /                       xfs
>> defaults,discard 0 1
>>
>> /dev/sda2 on / type xfs (rw,relatime,attr2,inode64,noquota)
>>
>> fstrim shows that trim is at least enabled, but I am unable to confirm if it
>> is done in realtime, or I am required to run fstrim manually.
>>
>> # fstrim -v /
>> /: 48919015424 bytes were trimmed
>>
>> Can anyone share some insight into this?
>>
>
> IIRC you have to rebuild your initrd so it picks up the new fstab
> mount options for /, the other options is you should be able to do
> mount -o remount,discard /.  Thanks,

Hi Josef,

This was the basis of my query - even after a remount with the discard 
option, 'discard' still wasn't present in the options - as seen by the 
mount line quoted above.

-- 
Steven Haigh

Email: netwiz at crc.id.au
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