--On Tuesday, September 16, 2003 11:17:07 +0100 Philip Hazel
<ph10@???> wrote:
> On Tue, 16 Sep 2003, Pat Lashley wrote:
>
>> No, that is disk blocks; which have been 512 bytes for a couple of
>> decades now.
>
> I've only been working with Unix for just over a decade; before that I
> was an IBM mainframe programmer, and disk blocks were whatever size you
> chose to make them. Before *that*, IIRC, on the Titan/Atlas system we
> used, disk blocks were 512 x 48-bit words...
Ok, it's been 25 years since I was an IBM mainframe programmer. I
had forgotten that they didn't use a fixed sector size. Ah yes,
the days of squeezing extra space out of a 5Mb frisbee(*) platter
by allocating one large sector per track. And trading that off
against only having 128Kb of main memory. (And no virtual memory
at all...)
(*) I don't remember the IBM model number for these removable
disks. It was a single platter about 18 inches in diameter, in
a round white plastic case. Hence the nickname. The IBM 360/44
had a dual drive for them mounted in the left side of the main
chassis behind the light-encrusted front panel. Unfortunately,
it turned out that vibrations from the drive motors tended to
loosen various chassis bolts. Which reputedly could cause a
head crash that would throw pieces of the head and actuator arm
out through the side of the box...
>> headers_replace Subject: [mumble] $h_subject
>
> Already WishListed:
I thought it sounded like too good of an idea to be original... :-)
-Pat
