Last week, we relayed information from Fudzilla indicating that Western Digital might be switching to SATA III for its 2 TB HD models as early as Q1 2010. The company denied this information however indicated that there will be indeed something new introduced next year. It will mostly remain invisible for the end user, this is however a major step in the HD industry as it will mark the end of a 30 years-old system: the way physical formatting of HD is carried out.
Since 30 years, all disc-based HDs have the same organization of data.
They are spread in 512 bytes blocks, with a header of each of them allowing its identification, as well as a specific sequence ECC at the end for checking integrity of the stored data. With the release of SSDs, a similar structure was maintained, but blocks are now of 4 KB, 8 times larger and aligning better with current needs.
WD will adopt the same structure for its 2 TB HD models released on 2010, and it will be applied to more models during the year. Such formatting block system have several advantages:
- Less headers and ECC translate into an increase of the usable storage space, from 7 to 11% depending on the HD.
- Improves burst error correction by 50% through the use of larger ECC (error correction code) code word.
- Improves error rate capability by 2 orders of magnitude and increases data integrity.
- Faster writing and reading performance
To maintain compatibility with these devices, Advanced Format media emulates a 512 bytes device by maintaining a 512 byte sector at the drive interface.
All current computer and OS can use such new formatting system without any changes, except Windows XP which will need a single use interpreter. At the end, the emulation layer will not be required anymore, speeding up performance too. One would need to find the ideal size of block to offer the maximum performance level for end users, a good mix between offering maximum capacity without losing to much time into writing small temporary files (smaller than the size of the block) by the OS.
