The dual processors that control data flow in the Caviar Black are common to all of the drives in the Black range and so too are the StableTrac and NoTouch features. These are, respectively, a mounting system that supports both ends of the motor shaft and a way of ensuring the heads don’t make physical contact with the platters.
Dual actuator technology is the result of a reworking of the end of each actuator arm:
Instead of mounting the read/write heads directly on the actuator arm, WD has added an extra component to the system. The read/write heads are mounted on a piezoelectric actuator that in turn is mounted on the arm. This means that the head can move across as many as five tracks while the arm remains in one position.
During our testing we found that the 2TB Caviar Black compares very favourably to the 1TB Black. File transfer speeds within the 2TB drive are considerably faster than the 1TB which suggests that the increases in cache, areal density and head reach flexibility have worked wonders. HD Tach shows that random access time has dropped by a healthy margin while read and write speeds have all improved to the tune of 20 per cent. CrystalDiskMark also shows a marked improvement for the 2TB drive.
HDTach 3 Readout
WD Caviar Black 2TB
WD Caviar Green 2TB
> CRC checks in the filesystem are a nice feature but they are only checks, they are not error correcting at all just error detection
You are wrong. ZFS detects *and corrects* errors. The 256 bit block checksums are compared with the data read back during a file read or scrub operation, and if an error is detected it is corrected using parity data in redundant vdevs.
If you don't believe this, try reading the ZFS tech info available -- look under 'self-healing'.
"The real annoyance is that Windows and Mac OS X both insist on measuring in GiB, but use the "GB" suffix like they're just trying to confuse you. Hence the icon."
Yeah, both major operating systems are trying to confuse you, not the HDD manufacturers. *sigh*.
Windows and Mac OS X have been *correctly* reporting in "MB" and "GB" since before MiB and GiB were even invented.
MB = megabyte (2^20 bytes)
GB = gigabyte (2^30 bytes)
MiB = Men in Black, a movie starring the Fresh Prince
GiB = Girls in Black, a little known blaxploitation sequel
"You can buy 1TB 2.5" drive ---- where???
I think the statement "You can buy 1TB 2.5" WD drive" is incorrect. 1TB 2.5" drive is still only a WD marketing dream and exists only as HTML page on Western Digital site. I cannot buy it neither from WD site nor from any other channel. Only 500GB drives on stock, same as half a year ago.
I think Western Digital managers developed and excellent way to get bonuses. If the product is not ready on time - just place nice description on web page, and you can put a plus sign that it is "released". When, in reality, half a year will pass until customers are able to buy the product.
I suggest to clearly mark all the pages where product is not yet on sale. I.e.: "Future product. Estimated availability date - December 2009."
You can have it all with OpenSolaris and ZFS...
Leo Waldock writes, "This is thoroughly good news but of course it’s the combination of performance allied to the colossal 2TB capacity that catches the eye. That said, the formatted capacity is a ‘mere’ 1863GB."
Under OpenSolaris with ZFS - you will have more of the 2TB potential, if you are running with redundancy, since ZFS can perform the error correction for you, instead of being done on the disk drive... no sense in doing the error correction twice and losing the space twice when the loss of space in CRC's is redundant...
Generally wikipedia is not a place to go quoting. At the same time if you read what it did say, the filesystem overhead is less than 1% of the space. The difference between 2000GB and 1863GiB is a lot more than 1% (6.8% in this case). So it has nothing to do with the filesystem overhead or formatting or anything else, it is simply a matter of the HD makers and Microsoft using different units. Back when harddisks were measured in MB the difference was smaller and many people just claimed it was the overhead of the filesystem, even though it wasn't true then either. Now that we are starting to see rather large differences people actually start to really notice it. If you were to convince windows to show you the size in bytes instead of GiB then you would still have a capacity of the filesystem even with the filesystem overhead of very close to 2000000000000 bytes.