Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!rutgers!apple!well!wdh
From: wdh@well.sf.ca.us (Bill Hofmann)
Newsgroups: comp.sys.mac.programmer
Subject: Re: MoveHHi or NewPtr? Which end of heap?
Message-ID: <21922@well.sf.ca.us>
Date: 2 Dec 90 18:38:36 GMT
References: <1990Nov30.013939.18568@midway.uchicago.edu>
Distribution: usa
Organization: Whole Earth 'Lectronic Link, Sausalito, CA
Lines: 20

In article <1990Nov30.013939.18568@midway.uchicago.edu> fri0@quads.uchicago.edu (Christian E. Fritze) writes:
>I've got ~75K of sound resources which I load into memory early during startup
>of my application. These resources are accessed continually during operation
>of the app, so I will lock them down in memory for use.
>
>Question: Is it preferable to lock these away high (after a MoveHi(hndl)) or
>instead to try and allocate a nonrelocatable block at the beginning of the
>heap with NewPtr()? Which end of the heap is better? Many thanks.\

The answer is, whichever produces the least fragmentation.  Using a resource
(which gets loaded in as a handle, BTW), and MoveHHi/HLock seems to be a bit
better, since typically, if you have a separate segment for your init code, 
you'll UnloadSeg it when you're done, but then you'll leave a hole in the
heap before your non-reloc block holding the sounds.  Of course, MoveHHi
won't move a reloc block above a locked block if one's in the middle of the 
heap.  When I run into this kind of question, the way I approach it is to
carefully step through my init code with MacsBug or The Debugger or TMON
and watch what's going on, and adjust code to produce the desired results.

-Bill Hofmann