On Thu, Apr 26, 2012 at 12:59 AM, Emmanuel Noobadmin
[off-list ref] wrote:

On 4/25/12, Alex [off-list ref] wrote:

quoted

I can see that you are trying very hard to fit a new picture into an old
frame. But with new technology there is always new possibilities. For
example, what I am thinking is: with the new laser write head, it doesn't
necessarily require the head to stay very close  to the platter since laser
doesn't fade away with longer distance, which may enable a design that

The strength of the laser will fall as the distance to the media
increases, wouldn't it?

Thanks for David answering this for me.

quoted

the head turns(the platter doesn't have to be round) instead of spinning
 the platter; hence the "Data rate is a product of [density * RPM]"
statement falls apart. What is more, if the cost is justified, one may
even design a disk with multiple write heads to increase the bandwidth
since now we are free from the fluid mechanic interaction between the
head and the platter. Both of these may lead to independent increase
of data rate. I am having these thoughts because it's been an endless

But Ostler's technique only increases the write speed and admits in a
Wired.com article there is still no faster/other way to read the data.
So we would still be stuck with the rotating disk and the magnetic
reading heads until some other breakthrough happens.

Ostler admits that in his response to my e-mails too.

Going back into the context of parity RAID rebuild, we would still be
bottlenecked on the write side wouldn't we since bits on the
replacement drive can only be calculated after reading the rest of the
drives.

Yes if we can't make reading as fast as writing. But in general having a
disk with write speed faster than read speed might still be an interesting
choice for applications with a lot of disk write.

Cheers,
Alex
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