Cost of DVD as data storage versus HDD (UK)

In article , "half_pint"
says...
snip
However what you fail to realise is that data just behind the read head
requires one revolution for it to be read (unless it has multipule read
heads).
So my 5400 is only about 33% slower than a 'modern' 7200 drive.

A fact which even the most persistant of trolls cannot deny.

That's the maximum time that the head will take to start reading the
data after it has been positioned over the track. You have not taken
account of the time for the head to position over the track or the speed
of data transfer once it has started reading.

"guv" wrote in message
...
[snip]
Seeing as the density of data is far more in a modern multi-platter
drive, the amount of data read in one revolution will be so much more,
[...]

If you look at a family of drives where the only difference is the number of
platters, or rather, heads, you will find no difference in performance. I
assume this is because only one head is used at a time, even though all
heads move in unison.

Alex

guv wrote:

On Fri, 29 Oct 2004 01:15:41 +0100, "half_pint"
wrote:

A fact which even the most persistant of trolls cannot deny.

Since I'm not a troll and you refuse to post as requested the drive
model number to PROVE what you are suggesting is nonsense, perhaps you
would like to prove this point incorrect and do so? Or will you just
continue to ignore this as you have previously?

half_pint (and his previous incarnations) is deranged. He refuses to
comprehend or accept any sense people talk to him.

There is no point trying to enlighten him, just kill file him, life is too
short.

On Fri, 29 Oct 2004 00:56:22 +0100, "Simon Finnigan"
wrote:

I`ve NEVER heard of it being described as a bathtub shape. How long ago was
your education, out of interest? What type of statistics would you use to
describe the failure rates? Everytime I`ve ever seen the relevant type of
stats being used, it`s always been a bell shape. Adjusting the parameters
could just about come up with a very weird bath-tub shape, but it`s
certainly nothing like a bath-tub as I know it :-)

He's obviously talking about the failure rates for the IBM Deskstar
drives...



--
Neil Maxwell - I don't speak for my employer

"Rob Morley" wrote in message
t...
In article , "half_pint"
says...
snip
However what you fail to realise is that data just behind the read head
requires one revolution for it to be read (unless it has multipule read
heads).
So my 5400 is only about 33% slower than a 'modern' 7200 drive.

A fact which even the most persistant of trolls cannot deny.

That's the maximum time that the head will take to start reading the
data after it has been positioned over the track. You have not taken
account of the time for the head to position over the track or the speed
of data transfer once it has started reading.

WEll they are not relevant to my point so obviously not.
But thanks for verifying that i am correct anyway.

"guv" wrote in message
...
On Fri, 29 Oct 2004 01:15:41 +0100, "half_pint"
wrote:

Your drive spins at either 5400 or 7200, the *same* as mine.

As has already been said *your* drive does *not* spin at 7200rpm.

Not what I said "Your drive spins at either 5400 or 7200, the *same* as
mine"

Miine spins at 5400 (5401 I think), which statisfies the the 5400 or 7200
clause.

And which by definition, you would agree that a modern 7200rpm drive
will out perform a 5400rpm drive?

At what?




Why not offer the info on the drive make and model, and we can
demonstrate with hard facts your assumptions on speed of throughput,
read and write are incorrect.

I would wager that even 4000rpm laptop drives far out perform your 7
year old 3 gig drive.

When I first started playing with analogue Video capture about 6 years
ago, only SCSI drives were capable of substained write capabilities
needed of about 7Mbps. Now, *every* IDE drive on the market can
*easily* cope with that and pass the figure needed probabily in excess
of 8 times what is needed.

Something that should be pretty obvious, the fact that technology
continues to improve in leaps and bounds. Something, everyone readily
accepts as a fact and easily provable with stats on the net. I can
only assume you are playing games if you cant see this to be the case
and are acting as a troll.


However what you fail to realise is that data just behind the read head
requires one revolution for it to be read (unless it has multipule read
heads).
So my 5400 is only about 33% slower than a 'modern' 7200 drive.

Seeing as the density of data is far more in a modern multi-platter
drive, the amount of data read in one revolution will be so much more,
the spin speed of your ancient drive becomes irelevant when trying to
suggest your drive reads and writes the same volume and speed as a
modern drive.


SO you agree that "my 5400 is only about 33% slower than a 'modern' 7200
drive."


A fact which even the most persistant of trolls cannot deny.

Since I'm not a troll and you refuse to post as requested the drive
model number to PROVE what you are suggesting is nonsense, perhaps you
would like to prove this point incorrect and do so? Or will you just
continue to ignore this as you have previously?

I have a Samsung and noisy Western Digital I an not going to dismantal
may computer, post your drive model number first.



--
www.senaction.com

"Alex Fraser" wrote in message
...
"guv" wrote in message
...
[snip]
Seeing as the density of data is far more in a modern multi-platter
drive, the amount of data read in one revolution will be so much more,
[...]

If you look at a family of drives where the only difference is the number
of
platters, or rather, heads, you will find no difference in performance. I
assume this is because only one head is used at a time, even though all
heads move in unison.

Good pooint Alex, I was just about to say that!!!



Alex

"nospam" wrote in message
...
guv wrote:

On Fri, 29 Oct 2004 01:15:41 +0100, "half_pint"
wrote:

A fact which even the most persistant of trolls cannot deny.

Since I'm not a troll and you refuse to post as requested the drive
model number to PROVE what you are suggesting is nonsense, perhaps you
would like to prove this point incorrect and do so? Or will you just
continue to ignore this as you have previously?

half_pint (and his previous incarnations) is deranged. He refuses to
comprehend or accept any sense people talk to him.

There is no point trying to enlighten him, just kill file him, life is too
short.

Your life will be pretty short with that kind of attitude to wisdom.

Never ignore wisdom.

SO you agree that "my 5400 is only about 33% slower than a 'modern' 7200
drive."

You are absolutely right! "5400 drive is about 33% slower than a 7200 drive"
is TRUE!
With accuracy of more than 99.7%.
Let me repeat: "5400 drive disk rotation speed is about 33% slower than disk
rotation in a 7200 drive"

You can also argue that 7200 drives are not more than about 25% better than
5400 drives. ;-)

half_pint wrote:


"nospam" wrote in message
...
guv wrote:

On Fri, 29 Oct 2004 01:15:41 +0100, "half_pint"
wrote:

A fact which even the most persistant of trolls cannot deny.

Since I'm not a troll and you refuse to post as requested the drive
model number to PROVE what you are suggesting is nonsense, perhaps you
would like to prove this point incorrect and do so? Or will you just
continue to ignore this as you have previously?

half_pint (and his previous incarnations) is deranged. He refuses to
comprehend or accept any sense people talk to him.

There is no point trying to enlighten him, just kill file him, life is
too short.

Your life will be pretty short with that kind of attitude to wisdom.

Never ignore wisdom.

If you had any to offer then you might have a point. But you don't. You
take one of at least four different factors that contribute to the
performance of storage devices, and on the basis of that one factor,
without any test results or calculations or literature citations or
anything else to support your argument conclude that you have proven
something about disk performance.

That is not wisdom of any kind.



--
--John
Reply to jclarke at ae tee tee global dot net
(was jclarke at eye bee em dot net)