Thoughts needed

[William E. Davidsen Jr]

In article <3771 at lynx.UUCP> m5 at lynx.UUCP (Mike McNally) writes:
| In article <230 at obie.UUCP> wes at obie.UUCP (Barnacle Wes) writes:
| >                               . . .  MS-DOS allows you to load your
| >program and write files on the disk in a fairly reasonable manner, and
| >won't get in the way of your response time (hopefully).  . . .
| 
| ``Reasonable'' is in the eyes of the reasoner.  Because (at least in
| the 386 thing we have here) the AT hard disk controller does not use 
| the DMA controller, the CPU must poll when transferring.  The MS-DOS
                      ^^^^^^^^^^^^^^^^^
| driver keeps interrupts off while doing this, bringing the interrupt
| response time down by quite a bit.

  As I'm sure a lot of people will tell you, that's the way the beast is
implemented, not the way it *must* be done. Xenix and OS/2 seem to be
able to run just fine using DMA mode and interrupts. The problem is that
MS-DOS is more or less a knock off of CP/M, and since it's not multi
tasking it has nothing better to do with the CPU than wait.
-- 
	bill davidsen		(wedu at ge-crd.arpa)
  {uunet | philabs | seismo}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me