Subject: Re: Memory allocation
From: [email-masked] (Dietmar Heidrich)
Date: 3 Feb 93 11:48:42 GMT
Newsgroups: comp.sys.amiga.programmer

In article    <[email-masked]> Doug Walker wrote:
> MEMF_PUBLIC does not mean anything.
>
> It has never meaned anything.
>
> It will never mean anything.
>
> This is because it is so badly misused that no system VM code could
> ever take advantage of it.  Any VM additions to the OS will not use
> the MEMF_PUBLIC bit.

I think I am going to correct this statement.  Here in Germany a public
domain VRAM-Manager has been published by M*rkt & T*chn*k that is using
this bit.  Memory allocated with MEMF_PUBLIC is not written to disk
during swapping.  For all programmers, follow this instruction:

Allocate anything except ports and other structures that need to be
shared by more than one process at the same time WITHOUT MEMF_PUBLIC.
MEMF_PUBLIC means this piece of memory MUST stay where it is.  Memory
allocated without public status is allowed to be swapped to disk.
There is also the condition that the memory has to be FASTMEM.  CHIP
memory cannot be swapped.

At least, using MEMF_PUBLIC with care and thought is a good style.

Dietmar Heidrich, Germany