[nobitacu]

The Inquirer has posted a method of getting massive amounts of hard drive space from your current drive. Supposedly by following the steps outlined, they have gotten 150GB from an 80GB EIDE drive, 510GB from a 200GB SATA drive and so on.

Here's the link:http://www.theinquirer.net/?article=14597

I'm not sure how this would work on a Mac, but wow, here's some results after they did it.

Interesting results to date:
Western Digital 200GB SATA
Yield after recovery: 510GB of space

IBM Deskstar 80GB EIDE
Yield after recovery: 150GB of space

Maxtor 40GB EIDE
Yield after recovery: 80GB

Seagate 20GB EIDE
Yield after recovery: 30GB

Unknown laptop 80GB HDD
Yield: 120GB

MIng

[nobitacu]

Well, just read about the follow up on the story. So I guess while it's possible to do this, you might not want to use that new found space anyways...

Ming



I am the "Linux SATA guy".

First, users are usually amused to learn that the capacity of modern hard drives is _unknown_, until it goes through the factory's qualification tests. The 120GB hard drive you purchased may have been physically identical to a 250GB hard drive, but simply it only passed qualification at 120GB.

Intel does the same thing with processors. A 3.0Ghz processor may be sold as 2.4Ghz, simply because it didn't pass qualification at 3.0Ghz but did at a lower clock speed.

Second, in the ATA standard there is a feature known as the "host protected area". This area is accessible from any OS -- but it requires special ATA commands in order to make this area available to the OS.

Third, all hard drives reserve a certain amount of free space to use for reallocation of bad sectors. These "spare sectors" are free space on your drive... completely unused until your hard drive starts finding problems on the physical media.

So this is old news Although the host-protected area (HPA) can be used for insidious purposes such as DRM/CPRM that is completely hidden from the users, most of the "invisible free space" exists for a purpose -- either it's spare sectors for bad sector remapping, or its capacity that didn't pass factory qualification, that you don't want to use anyway.

Feel free to edit/reproduce/publish this email.

Jeff Garzik

[ironknee]

i found that using panther, my hd is filling up but without many work files stored on it, i tried to backup/trash files but still the hd is almost full

[benb]

Originally posted by ironknee:
i found that using panther, my hd is filling up but without many work files stored on it, i tried to backup/trash files but still the hd is almost full

http://slashdot.org/article.pl?sid=0...37&mode=thread

Specifically:

What probably happens here is: ghost creates a special file, or at least writes to an empty part of your filesystem. Then, it writes a complete mini-os to this 8 MB region.

It backs up the original MBR (which is the bootsector, it also hold the partition table) and writes its own MBR. This MBR has a partition table which includes an 8 MB partion. The boundaries of the partition are the boundaries of the special file.

Since this MBR isn't meant to be used in any normal operation environment, it's not quite legal. Some (not all, the MBR can only hold 4) of the original partitions still show up in the new MBR. Therefore, the 8 MB partition lies inside a much larger partition.

This probably confuses fdisk, which lets you create a partition directly after the 8 MB partition, but inside your original partition.

When you subsequently delete the 8 MB partition, fdisk is probably confused again. The end of the original partition is probably obscured by the new, overlapping partition. So it lets you create yet another partition, from the beginning of the disk to the start of the overlapping partition.

The end result is: one large partition holding two small partitions inside it. This will exactly double your diskspace. Just don't try to use it :-)

[philzilla]

i got this error on an early build of Panther, it's not photoshopped. 10Gb drive, but i wish it was really as big as is being reported by Finder!

[Kenneth]

I am not going to take the risk.

[Scotttheking]

All it does is corrupt the partition table. It doesn't give you more space.

Edit: Fixed grammar.

[Ω]

Maybe the warning should go in the first post to stop people from attempting it before they know the facts?