Memory management of AmigaOS 4

[Mr.Grabber89]

hello sir, i have my project in our operating system class.. we have to make a documentation about the comparison of AmigaOS 4 and Nextstep operating system... the problem is i can't find any link or information about the memory management of amigaOS 4.... please give me information about the memory management of amiga... thank you... :afro:

[strim]

hello sir, i have my project in our operating system class.. we have to make a documentation about the comparison of AmigaOS 4 and Nextstep operating system... the problem is i can't find any link or information about the memory management of amigaOS 4.... please give me information about the memory management of amiga... thank you... :afro:

I wish I had classes like this!

Memory management of NeXTSTEP is typical for a UNIX (with some small differences, as it uses Mach kernel - just like MacOS X). It is characterized by heavy use of MMU, virtual memory, memory protection and other goodies . This document https://users.cs.jmu.edu/abzugcx/public/Student-Produced-Term-Projects/Operating-Systems-2002-FALL/NEXTSTEP-by-Wes-Deviers-William-Pope-Jeremy-Dunn-Shaun-O'Kelley-2002-Fall.doc contains some brief introduction to NeXTSTEP memory management.

AmigaOS is a completely different beast, albeit much simpler in memory management dept. I don't know any document summarizing how it works, but you should start with Amiga ROM Kernel Reference Manuals: http://gega.homelinux.net/AmigaDevDocs/ . Information you need is scattered through various chapters. This documentation covers version 2 and 3 of AmigaOS. Keep in mind that memory management in AmigaOS 4 has improved a lot, but basic principles are the same. New features are described here: http://www.intuitionbase.com/os4features.pdf .

I think that sole reason for your exercise is to show differences between management systems where memory is protected, and where it is not.

[jorkany]

Hyperion used to have a sparse explanation on their website, but now even that has been removed. But here is a thread on the subject which might have some more information about their version of "slab allocation":
http://www.amiga.org/forums/showthread.php?t=46360

Edit: I also would like to add, you may want to find a different class or instructor if they're using OS4 as a learning example. There's a real world out there and OS4 isn't part of it.

[kolla]

I wish I had classes like this!

You didn't? We had MSDOS vs. UNIX - and ofcourse Minix, since the book was Tanenbaum's Operating Systems: Design and Implementation

As discussed elsewhere... crash course to operating system development

[Argo]

http://amigaworld.net/modules/news/article.php?storyid=844

Might also try contacting the devs. Never know, you might be able to get a good quote or too.

[strim]

You didn't?

No, I had classes full of crap and bullshit, like explaining which icon in M$ Visual Studio should I click. Or how great C# is. In the end I had to learn real programming (C, UNIX, AmigaOS ) myself. Btw. Andy's book is really nice.

[Piru]

some more information about their version of "slab allocation"

Oh the old "slab glorification". It was so much fun reading about it back then, huge deal was made out of minor detail (it's only used to manage allocation of certain sizes).

Needless to say the truth was only revealed when some actual benchmarking was made. OS4 memory system proved to be as slow as snail.

It was adjusted later on, however, but the point is that just writing a lot of PR and using bunch of old concepts doesn't necessarily make a viable solution.

[Akiko]

Oh the old "slab glorification". It was so much fun reading about it back then, huge deal was made out of minor detail (it's only used to manage allocation of certain sizes).

Needless to say the truth was only revealed when some actual benchmarking was made. OS4 memory system proved to be as slow as snail.

It was adjusted later on, however, but the point is that just writing a lot of PR and using bunch of old concepts doesn't necessarily make a viable solution.

Your right on cue, let the bashing commence   :rolleyes: