Is Secure Erase in Mac the same as HDD Erase for P128GB?

If I have to erase SSD to return to default performance when the SSD P128 version VBM18C1Q degrades in performance, is the utility in my Macbook Pro mid-2009 for secure erase sufficient to do the job before re-install? Is there a simpler way to maximize performance without all of these acrobatics? One thread has said that Garbage Collection doesn't work on Mac OS?

thanks

No, it's not the same. In fact, if you run this on a new fresh drive, you will get the performance loss right away because secure erase writes to every block at least once.

The easiest way to get performance back is to download the gparted CD and run the hdutil as described in the sticky thread. You don't need to remove the drive from the computer, but you'll need an external USB drive for backup.

Here are the steps I would use:

- get GPARTED and google for a backup program named SuperDuper

- use SuperDuper to copy your hard drive to the external USB disk

- boot from the external disk to verify it works (hold down the Alt-key for a few seconds at power on)

- if booting from the external USB works, boot from the GPARTED CD and clear the internal drive.

- boot again from the USB backup drive, run SuperDuper to copy it back to your machine

Alternately you can do this

- use TimeMachine to make a backup to an USB connected drive

- boot from GPARTED and erase drive

- boot from your Snow Leopard CD and teill it that you have a Time Machine backup and let it restore

@shimodax:

why is secure erase on Mac OSX not the same?

As far as I know OS X writes Zero to every block when it´s secure erasing. Isn´t it the same what GParted do?

Just fill all Blocks with Zero? If I use use GParted to fill all Blocks with Zero and the Partition Table says that Blocks are empty, the secure erase on OS X does the same: Partition Table says that Block is empty and Block is Zero.

Can you please explain?

Greetz

Dirk

Could someone confirm that doing the secure erase with Mac OS, snow leopard, does not achieve the desired result of restoring the drive to default performance. I can do as directed above eventually, but it would be quite a bit easier to do the erase within the system I've got.

Thanks,

Not quite sure of your response. You say that using the Secure Erase in Snow Leopard, which I believe does write zeros on the drive, should work. Would writing these zeros in Secure Erase bring the drive back to full performance? You can't guarantee it, but someone else is claiming that writing the zeros in Mac Secure Erase is not the same as an erase.

Then you suggest using Parted Magic, which is much more complicated than simply doing full secure erase within the mac os and then re-installing the system and then transferring from Time Machine?

I don't understand.

Secondly, is it possible that rebooting and idling my Macbook Pro for one hour would self-cure the drive. Has no one at Corsair tried this or does someone know definitively that it doesn't work.

thanks

@Ram guy:

Secure Erase is not a utility for Snow leopard 10.6.

It´s in the system and you can enable it. Means: normally when you empty the trash only the Partition Table is erased. With secure-erase enabled, the Partition Table is erased and Block is overwritten with Zero.

Nobody at Corsair who can confirm this? I´m quite baffled.

So, would be nice to get a confirmation about Corsair SSD´s in Macbooks running Snow Leopard....

Cheers

Dirk

What HDPARM on the GPARTED CD does is to issue an erase command directly to the SSD controller. The Secure Erase function on the Mac on the other hand uses 'write' to put zeros to eachh block on the disk ... that is calling 'write' block by block.

So secure erase is actually the opposite of what you want to do with an SSD (ie. writing data to every block). It's similar to doing a full format (not quick format) on Windows.

Thanx Shidomax for that information!

So i will use GParted from time to time...

Secondly, is it possible that rebooting and idling my Macbook Pro for one hour would self-cure the drive.

From everything I read about the self-cure feature this will *not* work. It will only work if the SSD controller understands the format of the data in a partition and I never heard anything other than 'it only understands NTFS' (and the Mac doesn't use and can't even write NTFS).

Hi all,

I recover HDs for a living. I just learnt the hard way that using the erase free space feature is not good. My 13" MacBook Pro is now running like Molasses. Even keystrokes are delayed as I am typing this, so, don't do it.

Shimodax is right, if you erase free space using DU, you'll turn your drive into sludge, like I just did.

Critical Limit, it's because it writes, not erases. To get the speed back, the drive needs every register marked as clean, or empty, erased, whatever you'd like to say.

ejosepha, nope.

Ram Guy, nope, it doesn't sadly.

Critical Limit, actually Secure Erase IS a utility in Snow Leopard. It's accessed in Disk Utility. You're thinking of secure empty trash, which can be toggled by holding down the option key while emptying the trash, or setting the option in the Finder Prefs.

Lastly, the repair during idle command only works with NTFS formatted drives. This is the real thing Corsair/Samsung need to fix. The drive should repair itself when idle, constantly.

So I am downloading this Linux CD now and we'll see how we go. Because it wasn't like I had plans for Sunday anyway right!? *sigh*

Scratch that... Got GUI working...

But drive is frozen... How to unfreeze it? Anyone got it "not frozen" on a Mac?

To bypass the frozen SSD, you have to do the following.

WARNING-This may cause kernel panics/hangups so proceed with caution.

1) Power down system (Note - make sure your SATA controller is in IDE Mode)

2) Attach SATA cable to drive in question - DO NOT connect power

3) Power on system

4) Fire up GParted or your DOS boot disk for HDDErase.

5) Connect power to the drive.

6) Proceed with Secure Erase.

OK, so finally got my p256 cleared out and reloaded. Much faster now.

I realize though that I should be keeping as little data on the SSD as possible. Can anyone confirm that the SSD will continue to use genuinely free space until it is all gone and only then begin to erase empty portions for rewrite?

If that's the case, I'll keep less than 128GB on this 256GB drive and hopefully extend its usable time quite a lot.

What a PITA though!!

I am thinking that Corsair may need the same prodding Apple usually needs in order to listen to their customers - a class action lawsuit.

To bypass the frozen SSD, you have to do the following.

 

WARNING-This may cause kernel panics/hangups so proceed with caution.

 

1) Power down system (Note - make sure your SATA controller is in IDE Mode)

2) Attach SATA cable to drive in question - DO NOT connect power

3) Power on system

4) Fire up GParted or your DOS boot disk for HDDErase.

5) Connect power to the drive.

6) Proceed with Secure Erase.

On a Mac you can hold down the Alt key at power on (keep it pressed until you hear the first chime) to select the media to boot from. Detaching/Attaching the cables while powering on is close to impossible on most macs because you need to dismantle them to get there.

On a Mac you can hold down the Alt key at power on (keep it pressed until you hear the first chime) to select the media to boot from. Detaching/Attaching the cables while powering on is close to impossible on most macs because you need to dismantle them to get there.

Yeah, that won't make any difference. The drive will still be frozen.

I had to take the back off my MBP and run it on its side, boot with no drive, then plug it in. Then it's unfrozen. Only way to do it sadly.

And be careful, the screws on the MBPs thread very easily.

I should note that the procedure I listed is best NOT done in a notebook or laptop of any make and model. Wasted a good 2+ hours figuring out that on my laptop. That and Intel's PM45 chipset doesn't like running out of ACHI mode for whatever reason. :confused:

Hijack someone's tower to do the job - quick, easy and you'll be back at it before you know it.

If you have to, ask forgiveness later. :D:

I should note that the procedure I listed is best NOT done in a notebook or laptop of any make and model. Wasted a good 2+ hours figuring out that on my laptop. That and Intel's PM45 chipset doesn't like running out of ACHI mode for whatever reason. :confused:

 

Hijack someone's tower to do the job - quick, easy and you'll be back at it before you know it.

 

If you have to, ask forgiveness later. :D:

I did it on my 13" MBP.

Glad to hear it worked for you!

It's one of those YMMV things...either that or my laptop is very very picky.