[CentOS] Re: Where is cached memory going?

Tue Aug 19 20:37:29 UTC 2008
David Dyer-Bennet <dd-b at dd-b.net>

On Tue, August 19, 2008 12:06, William L. Maltby wrote:
> On Tue, 2008-08-19 at 11:50 -0500, David Dyer-Bennet wrote:

>> I don't recall that anybody referred to "DASD" connected to our IBM
>> 1401;
>> it was just "disk".  Were we just a weird corner (I wouldn't swear they
>> didn't use some weird term like DASD in the manuals, just that none of
>> the
>> people I worked with used it)?  Or was that a later term, say from the
>> 360
>> generation?
>> (When I worked on the 1401, we were in fact well into the 360 generation
>> chronologically, just not at the place I was working; that was in 1969,
>> and we moved from the 1401 to a DEC PDP-11/20 just a couple of years
>> after
>> that.)
> Ditto here. But our 1401 stuff was being emulated on S360/30. During
> that time, DASD became the lazy acronym used extensively to cover any of
> the then-extant direct-access devices (drums, cylinders, "disks" -
> euphemistically mounted in "pizza ovens (2314/19 IIRC).

We emulated the 1401 on the DEC 11/20 for a while, first with a standalone
emulator, later with a run-time system that integrated into RSTS and let
us run the 1401 applications under time-sharing.

I think of drums as being generally *before* then, and what are cylinders
that differs from drums?  But it *does* actually make sense to have a
generic term for that class of storage; we just didn't have enough
examples to need it, and "DASD" sounds stupid :-), and as an IBM mainframe
term wasn't something we wanted to emulate.

I suppose we're getting a bit far off-topic, but thanks for the stroll
down memory lane!
David Dyer-Bennet, dd-b at dd-b.net; http://dd-b.net/
Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/
Photos: http://dd-b.net/photography/gallery/
Dragaera: http://dragaera.info