HD formatting trouble

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mystran

Re:HD formatting trouble

Post by mystran »

Candy: Did I get it right that we can access 4TB with LBA?
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Re:HD formatting trouble

Post by Candy »

mystran wrote: Candy: Did I get it right that we can access 4TB with LBA?
Yes and no. (just love to answer with both answers)

Yes, you can use LBA for 4TB. You can even use it for 2^28 * 2^28 * 2^9 bytes, being 2^65 bytes, or roughly 32 exabytes.

No, you can't use what most people think LBA is. If you think it's the standard defined over 4 years ago, you're wrong. That's the 128GB limit exactly (2^28 * 2^9).

The trick is that the second 2^28 is achieved by sending two packets per request. You first send the extra bits, then the original bits and the combination of the two is used for loading the sector. Since the bandwidth of the channel way outperforms the disk itself you don't or barely notice this delay and can use it as if it was normal LBA.
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