[CentOS] Trouble (?) reformatting flash drive to include former U3 partition

Robert Nichols rnicholsNOSPAM at comcast.net
Tue Jun 16 17:35:49 UTC 2009

MHR wrote:
> On Mon, Jun 15, 2009 at 8:14 AM, Robert
> Nichols<rnicholsNOSPAM at comcast.net> wrote:
>> Sure.  I'll try it as a small attachment here.  It that doesn't
>> work, and I suspect it won't, I'll have to find some spot where
>> I can upload it.  I don't have anything like that set up just now.
> Got it - thanks.
> One thing I noticed when I formatted the drive with the 31/31/99212
> format was that it was REALLY REALLY SLOW!
> I don't really know enough about the driver for USB flash drives, but
> I would bet it has something to do with the high cylinder count, and I
> noticed the Sandisk's format, though short by 77+MB seems to be
> optimized for real disk drive timings - maximum sectors per track,
> maximum heads per cylinder, minimum cylinders.  In a real disk drive,
> this is wise because the inter-cylinder seek time is the longest
> (switching sectors is usually trivial, and switching heads is not much
> more).
> If that's true, the the "most" optimum format for this drive would be
> 124/31/24803.  Of course, that "loses" 124 sectors for the MBR, but
> that a whale of a lot less than 77MB.
> I could be totally wrong about this - haven't tested it yet.
> One last question, which I believe I did ask originally but didn't see
> any answer - anyone know why the Kingston is larger than the Sandisk
> (probably just designed that way - bravo, Kingston!)?

Heck, I've seen slightly different sizes among samples of the same
model of the same brand purchased at the same time.

It really surprises me that CHS geometry changes would have any effect
on the speed of the devices.  All accesses are being done with LBA.
Nothing is using CHS addressing, which wouldn't be able to go beyond
cylinder 1023.

Bob Nichols     "NOSPAM" is really part of my email address.
                 Do NOT delete it.

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