Mailing Lists: Apple Mailing Lists
Image of Mac OS face in stamp
 
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Darwin disk I/O - better interactive response

On Sat, 20 Jan 2001 11:24:12 -0800, Dave Yost wrote:
> I claim that in a personal computer such as the Mac (as opposed to a
> time-shared batch-ish system such as unix),

Dave, whatever you might contribute to Darwin will be more valuable if you
stop assuming that everyone is going to be using Mac hardware the way you
currently do.

> fast interactive response to the most-recent user interface gesture should
> be highest priority (after hard real-time requirements have been met, such
> as playing a sound file without interruption).

That's a reasonable goal for a personal computer.

Certain aspects of Darwin-- the preemptive multitasking, good SMP and thread
support, the Mach VM system, userland page selection (potentially, anyway),
non-blocking I/O make it possible to develop user interfaces which have great
"interactive" feel.

However, the Finder/Workspace is not a part of Darwin; I assume it is
off-topic for this list.

> I further claim that the above goal requires that disk I/O scheduling be
> prioritized and preemptive, just as processor scheduling is, even more
> importantly because of the vastly slower performance of disk vs. cpu.

There isn't a simple correlation between system responsiveness and your
notion of prioritizing disk I/O.

-Chuck

Chuck Swiger | email@hidden | Sturmbannfuhrer BOFH
-------------+-------------------+---------------------
Pavlovian slaver at the cash till ring of success... _M

References: 
 >Darwin disk I/O - better interactive response (From: Dave Yost <email@hidden>)



Visit the Apple Store online or at retail locations.
1-800-MY-APPLE

Contact Apple | Terms of Use | Privacy Policy

Copyright © 2007 Apple Inc. All rights reserved.