OS X Lion Disk Utility - "Erase Free Space" option greyed out

I'd not noticed that, and am not on Lion at the moment.

But it's not a good idea to do that on the volume you're running from. OSX collects all the empty space into a huge folder (so the free space on the disk goes to zero), then writes zeros to it, and releases it as it does so. That will take a very long time (241 GBs, in your case). If something goes wrong, or you cancel it, it can be rather difficult to get it to release the space.

It does not gain you any space; all it does is prevent the leftover data from files you've deleted and emptied the trash from being recovered.

If you really need to do it, use the Recovery HD. See Using the Recovery HD.

You most likely will need to boot from the recovery partition and invoke Disk Utility that way.

I am running Lion and Erase Free Space button is not ghosted in disk Utility for my system drive. So I would say that something is really differnent about your Mac.

Exactly what do you hope to gain by eraseing free space? Personally I have never found any reason to use it.

Allan

Chryssanthacopoulos wrote:

. . .

I'm not interested in erasing the free space on my disk, at least not at the moment. I am concerned that either my OS or disk are not functioning properly.

What symptoms are you experiencing?

Hi Chryssanthacopoulos. I'm experimenting exactly the same problem on my MacBook Pro with an SSD (Vertex2) inside.

Other users on other french forums had the same problem too. So you are not alone.

I contacted Apple and for the moment they have no solution. A Senior Advisor is working on the issue, but most probably it could be a Lion's bug.

yeah i have the same issue on my imac with a SSD in it, the option is greyed out.I never experiended this problem with snow leopard

In fact, after discussion with the Apple senior advisor, this is not a bug neither an issue.

Apple did activate the TRIM function by default on all (his own) SSD's, so the "Erase Free Space" command is not useful any more on SSD's supporting TRIM.

It's just logical.

What is less logical, is the fact that only Apple SSD's are TRIM activated by default, not any SSD's.

There is of course, as you know, a workaround to activate TRIM on any SSD (look for TRIM enabler on macupdate.com).

Just to keep you updated :-)

This cannot be done through the recovery partition either. When using disk utility from the recovery partition, erase free space is not available for any of the following reasons: 1) same reason cannot do it while on the primary partition. because apple thinks its not needed anymore or 2) because the recovery partition doesn't know the drive supports TRIM. the primary has been hacked to turn on TRIM, but recovery doesn't know about that.. and therefore, cannot support "erase free space" for the drive.

My concern is that I have been using an Apple SSD and I want to possibly sell it and the laptop containing it. I found this thread as I, too, see a greyed out Erase Free Space button from within Mac OS X Lion

After reading your post that this greyed out button is neither a bug nor even an issue due to the fact that TRIM support is activated on all Apple SSD disks, is it true that all files I've deleted from this SSD in the past are magically now as un-recoverable as the Snow Leopard Erase Free Space 7-pass DoD compliant wipe?

The last thing I want is any of my old files being recoverable by someone who buys my SSD drive.

You can do the secure erase of you do not boot from the SSD. So take it out, put in different mac or computer, and erase it from there.

This is the same as it was in SL by the way. You couldn't secure erase a drive you were booted from.... (of course)

Since posting my last reply, I've created a new parttion on my SSD and installed Mac OS X Lion. I've then booted from both partitions and regardless of where I boot from the Erase Free Space button is still greyed out for either partition: mounted or not. I can post screen shots if that would be helpful.

Why are you trying "erase free space"? I thought you wanted to erase the entire partition in order to be able to sell it? When booted from a different partiiton, the "erase" button should (hopefully) be available, not the "erase free space" button. "erase" is not available? That really wouldn't make sense... there has to be a format option! You configure the security of the erase by clicking the security button (where you can select your DoD stuff).

I wanted to Erase Free Space while I have it and potentially keep the existing OS install.

The Erase button is available and active.

Well as previously stated, erase free space button is no longer available. It can however be done two different ways. one is running fsck -ffy from single user mode. the other is by booting save mode (hold shift while booting)... and maybe have to hit some more buttons (I forget).

the button being disabled has nothing to do with you being able to sell the SSD. erase is still available. those are two completely different issues. None of which is a deal breaker really.