Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cbmvax!jesup
From: jesup@cbmvax.commodore.com (Randell Jesup)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Help --> How to prevent the visit from the dreaded guru
Keywords: Flip answers are no help
Message-ID: <17157@cbmvax.commodore.com>
Date: 7 Jan 91 03:32:30 GMT
References: <17130@cbmvax.commodore.com> <7465@sugar.hackercorp.com> <17133@cbmvax.commodore.com> <1991Jan6.032929.1813@mintaka.lcs.mit.edu>
Reply-To: jesup@cbmvax.commodore.com (Randell Jesup)
Organization: Commodore, West Chester, PA
Lines: 47

In article <1991Jan6.032929.1813@mintaka.lcs.mit.edu> rjc@wookumz.ai.mit.edu (Ray Cromwell) writes:
>
>  On a side note Randell, how difficult would it be to add Resource
>Tracking to the Amiga? Couldn't each library's close routine make

	ancient idea, can't be done without a bunch of new routines (dups
of all those that don't track), since you existing things can't handle it.
You also have to be careful about things that _shouldn't_ be released on exit.

> Virtual Memory shouldn't be a problem either. The OS merely checks for
>the presence of an MMU and enables virtual mem (for FAST mem. Its impossible
>to protect Chip mem from the blitter. And I can't imagine a machine
>with an MMU that doesn't have fast ram)

	Not so simple, at least in implementation.  Some things (for various
reasons) should NOT be paged out (remember this is a semi-realtime OS, it
will suffer badly if certain things are paged out).  However, not real
read.

>MMU Protection. I'm fairly certain AmyDOS will never get Unix style
>protection because of the shared-memory paradigm. But how about this
>. AllocMem(blah,MEMF_PRIVATE)  

	A few things could be protected.  Not much without breaking things,
and would require a lot of code and MMU tables per-process.

>1) Has layers library been speeded up/reworked? It gets really slow
>when there are lots of open windows on the screen.

	Yes.  Still slow in bad cases (not much one can do about it).

>2) What happens when you pull down a screen (on 2.0) and a productivety
>mode screen is behind it? Can monitors actually handle scan rate changes
>mid screen? (15khz <-> 31khz)

	Magic. :-)

>3) Was file notification/record locking ever added to the 2.0 FS?

	Both are active in recent releases.

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.commodore.com  BIX: rjesup  
The compiler runs
Like a swift-flowing river
I wait in silence.  (From "The Zen of Programming")  ;-)