Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!pasteur!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Memory Types???
Message-ID: <8804182055.AA15423@cory.Berkeley.EDU>
Date: 18 Apr 88 20:55:48 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 40

:    Can someone please tell me the proper memory nomenclature?  What I want to
:define are three different catagories of memory request:
:
:                CHIP   :   must be chip memory.

	ptr = AllocMem(bytes, MEMF_PUBLIC|MEMF_CHIP);
:
:                FAST   :   must be fast memory.
:
	ptr = AllocMem(bytes, MEMF_PUBLIC|MEMF_FAST);

:                FSCH   :   fast if possible, if not the chip if possible.

	ptr = AllocMem(bytes, MEMF_PUBLIC);

	I.E. EXEC searches for space in fast memory before chip memory.

:
:    Right now, these are always private to the requesting task.  I'd like to
:set up the memory allocation system so that it returns memory as fast as
:possible and has reasonalbe garbage collection and defragmentation capability.

	Unless you intend to go for double-indirect pointers, the EXEC
memory system defragments as much as is possible without moving already-
alocated chunks around.

:
:    Also, I am considering forcing longword alignment.  Since I am already 
:using 8 bytes for link fields and these really should be on lw boundries it
:seems worthwhile to me.
:
:                                                        Thanks,
:
:
:                                                              Wade.

	The EXEC memory system always returns memory on 8-byte boundries
(double longword boundries).  As far as I can tell, unless you want to
use double indirect pointers, the EXEC memory system is the way to go.

			-Matt