Possibility of hdparm on Mac OS X

[Scott Haneda]

On Aug 27, 2010, at 12:31 AM, Ned Deily wrote:

> In article <6EB398EB-F4ED-4A75-A5CC-F4A3447584EF at newgeo.com>,
> Scott Haneda <talklists at newgeo.com> 
> wrote:
>> The one command I am after is ATA Secure Erase, the rest would be nice, but 
>> that is the main one.
> 
> Doesn't Apple's /usr/sbin/diskutil provide this already, i.e. its 
> secureErase function?  (see "man 8 diskutil")

Unfortunately no.  The command I am after, ATA Secure Erase is not quite the same as the one built into Mac OS X.  It is, I believe, only useful and targeted to SSD drives.  SSD drives will start with a certain measure of performance that falls off by about 15% over use in the next week to month.  It then flatlines around that point for some time.

If you want your drive to work as fast as it was when it was new, you need to run this command against it.  This will write out the drive in a certain way that SSD drives are able to perform like new.  A Mac OS X Secure Erase, I believe, would only erase the drive, and add additional wear to it, actually making you worse off than you were before, albeit in a very minor way.

https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase
-- 
Scott (* For off-list contact, replace talklists@ with scott@ *)