Ron Hawkins pisze:
Perhaps there is more to the emulation of CKD than the thread touches on.
Disk Drives stopped recording in CYLS some time ago because the time for
head switching is greater than the minimum seek time. Drives today record in
a serpentine method across the platters, doing a switch-back (best word I
can think of) to the next head at intervals defined by the HDD designers.
The whole idea of tracks and CYLS is really dead and buried as far as the
real hardware is concerned.
Last but not least: there is no more "canonical geometry" - I mean fixed
number of bytes (sectors) per track. The longer (physically) track the
more bytes it keeps. All we know formula O=2*PI*r.
However even "the most modern" operating system like Unix or Windows do
not know about it. The systems still treat disk like it would have fixed
(equal) capacity tracks. They have to, because drive electronics still
cheats (emulates) "canonical geometry".
Talking about future we should also consider non-disk devices (flash SSD).
--
Radoslaw Skorupka
Lodz, Poland
--
BRE Bank SA
ul. Senatorska 18
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Wedug stanu na dzie 01.01.2009 r. kapita zakadowy BRE Banku SA (w caoci
wpacony) wynosi 118.763.528 zotych. W zwizku z realizacj warunkowego
podwyszenia kapitau zakadowego, na podstawie uchway XXI WZ z dnia 16 marca
2008r., oraz uchway XVI NWZ z dnia 27 padziernika 2008r., moe ulec
podwyszeniu do kwoty 123.763.528 z. Akcje w podwyszonym kapitale zakadowym
BRE Banku SA bd w caoci opacone.
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