Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!apple!oliveb!amiga!boing!dale
From: dale@boing.UUCP (Dale Luck)
Newsgroups: comp.windows.x
Subject: Re: Contents of windows
Keywords: LoTech
Message-ID: <729@boing.UUCP>
Date: 3 May 89 17:38:02 GMT
References: <4434@stiatl.UUCP> <4037@ficc.uu.net> <8078@phoenix.Princeton.EDU>
Reply-To: dale@boing.UUCP (Dale Luck)
Organization: Boing, Milpitas, Ca.
Lines: 44

In article <8078@phoenix.Princeton.EDU> mbkennel@phoenix.Princeton.EDU (Matthew B. Kennel) writes:
>In article <4037@ficc.uu.net> peter@ficc.uu.net (Peter da Silva) writes:
>
>Can the Amiga run the whole server and clients in 512K of memory, when
>that 512 also includes the frame buffer???  It MUST have shared libraries
>then, which many Eunixes seem to lack.

Yes, the amiga was one of the pioneers in dynamically loaded sharable
reentrant libraries.

>
>I think the Amiga's choice to make backing store available for every window
>and then return errors when it's out of memory seems like a mistake: I would
>rather have things work but run slowly than crash quickly.  By extension, 
>why have virtual memory at all?  Just return an error code when it runs out.

Where does crash come in? In most cases when you are low on memory it is
the user that is playing around with the windows. If they try to move or
resize a window and see that it does not move, they usually realize they
are running low on memory.

But actually this whole discussion about saving bits instead of dropping
the bits off the table as a matter of policy is not the issue at all.
The issue is what do you do when you run out of a resource to do an
operation. Memory is just one of those resources. There are plenty of
other gotchas in X when it runs out malloc memory. So those requests
seem already bound for a possible failure return.

>
>Another question: does backing-store only apply to the visble parts of the
>window, or could you conceivably make a gigantic window that you only
>see a little bit at a time.  If backing-store were required for the whole
>window, this would be bad news.

Usually backing store is only needed for the obscured parts of the window.
If you don't need backing store then don't ask for it. User's of machines
that have real memory limitations get quickly acustomed to the limitations
and how to get around them, as long as it does not crash and gives them
a chance.


-- 
Dale Luck     GfxBase/Boing, Inc.
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