Marten from the Kraats wrote:
>I am trying a pretty fast hard disk in a LC... Which format
>interleave is the best: 1, 2, 3, 4???
I have no direct answer to your question. But, since the concept
of "interleave" perplexed me for so many years... I thought I'd toss
in a few words on it for the benefit of "New Mac (real computer)"
users.....
Interleave is how the hard drive writes data:
A hard drive has a platter which contains (in terms of data) many
cylinders, or, tracks. Each cylinder is then sub-divided into blocks,
or, sectors.
For the sake of simplicity, let's take the number 10, since all
Western numbering systems are based on 10... Say, you have 10 sectors
of data on each cylinder...
Under ideal circumstances, your hard drive will read sector 1 (OK,
it's actually sector 0... But, this is for simplicity's sake) send
the data to your computer, the computer will then store the data,
then send a message to the hard drive, "OK, I'm ready for the next
block of data." This message will reach the hard drive at, or, before
the time the hard drive reaches the beginning of sector 2. (the time
it takes the platter to physically rotate to that point) This would
be a 1:1 interleave ratio.
In the case of a slower computer and/or faster hard drive... by
the time the computer stores the data from sector 1, then sends the,
"OK, I'm ready" message to the hard drive, the hard drive has already
rotated past the beginning of sector 2. Thus, the hard drive must
wait for the platter to turn one entire revolution before sector 2
reappears. Then it can send sector 2 to the computer. This slows
things down a whole lot...
In this case, it would be faster if the hard drive wrote data on
sectors 1, 3, 5, 7, 9, 2, 4, 6, 8, 10... By the time the computer is
ready for the second block of data, the hard drive is already past
the beginning of sector 2, but, the second block of data is written
on sector 3. So, the hard drive only has to rotate its platter 1/10
of a turn before it locates the data which the computer is ready for.
This is a 2:1 interleave ratio.
Much slower computers/much faster hard drives may require a 3:1
ratio... writing data on sectors 1, 4, 7, 10.....etc.
I hope this helps someone's understanding, somewhere.
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Since Judgement Day has now come and gone, it is now up to
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of "tribulation" to prove their True intent, or, be lost...
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