[sldev] Script/Parcel/Memory Limits - Memory Limit Configuration

[Dzonatas Sol]

Argent Stonecutter wrote:
> That hasn't been true for twenty years. Even back in the Amiga's day  
> it was common to copy the OS from ROM to RAM for a performance boost.
>   

Only when they came out with pseudo-fast memory, which made the 
difference between "Fast RAM" and "Slow RAM" based on what the CPU 
controlled.

> The Amiga blitter had nothing to do with ROM vs RAM.
>   

The CPU & Blitter locked memory, this was known as Chip RAM, which is 
analogous to DMA on i386 based CPUs. Psuedo-fast was fast because the 
Chip-set (blitter) did not lock it. Remember that your billboard idea 
for avatar imposters  was actually all done as hardware sprites on the 
Amiga.

It's the same principle in modern OSs, but its done more in software 
than in hardware except for what video cards still do today.

With newer memory cache schemes for multi-core CPUs that are headed to 
replace the "shared" memory architecture between CPUs and other devices 
on the motherboard that we have known, most of the fast and slow memory 
concepts can be expected to become obsolete.

> The Amiga OS also didn't run out of ROM, it ran out of what was called  
> "kickstart" memory, loaded by the kickstart ROM from the kickstart  
> disk. Kickstart memory was RAM.
>   


That was optional. As you can see many people used Kickstart ROM chips 
instead of diskettes. http://en.wikipedia.org/wiki/Amiga_500#Memory_map

Yes, people actually bought chip upgrades to boot/start Workbench 
instead to avoid the undesirable routine to have to find the kickstart 
diskette, load it, boot, and then reload their next flavor of diskette 
based software. Slow RAM with battery backup power was then used to 
upgrade that routine beyond the ROM sets that could be bought.


Anyways, the concepts of fast and slow memory is real, yet since it has 
become a major "no-no" to "hack the hardware" (a.k.a direct 
peeking/poking the hardware), like what used to be so common, the 
concept has faded, but not enough to criticize someone publicly on a 
list like it never existed.

In fact, both Intel and ATI have wanted to put Havok on a chip-set much 
like the Amiga's Chip-set or how any video now does video. That would 
essentially change the way scripts memory relates to physical 
simulation. Scripts with physics heavy procedures could be pinned to the 
Havok memory area. That's just all done in software now, so the 
distinction is just not being made obvious.