Z3 Fast safeguards

[BlankVector]

Hello.

This is about WinUAE 2.4.1.
I encountered trouble with Z3 Fast settings reported there.
So here is my wish list to improve the user experience.

1) Tell the user explicitly when VirtualAlloc() fails, with an error MessageBox. Something like "Your system does not have enough memory for the amount of Z3 Fast you asked for. Please decrease your Z3 Fast settings.".
Currently, if VirtualAlloc() fails, there is only a trace in the debug log, the user will probably not see it. Then the Z3 Fast is silently disabled, the user does not understand why there is no Z3 RAM at all. This is confusing.

2) It has been said that WinUAE is not able to increase the Z3 Fast size "on the fly", that is to say when starting emulation and pressing F12 afterwards, then Reset. This is an acceptable limitation, but the UI should not suggest that it is possible. Especially, pressing F12 and increasing the Z3 Fast size silently fails, this is not acceptable.
I propose the following: when F12 is pressed (by opposition to fresh startup), forbid the user to increase Z3 Fast to more than the initial value wich were used at startup. Or simpler, just gray out the Z3 Fast slider when F12 is pressed.

[Toni Wilen]

Do you have some use case where you need to change memory size on the fly?

1: Simple "halve size of memory, try again and so on.." can be done. (instead of just setting memory size to zero)

2: Approximate available memory space can be added to GUI (approximate because there can be "empty" space between different memory types)

(Actually I already did above changes..)

[BlankVector]

Originally Posted by Toni Wilen

Do you have some use case where you need to change memory size on the fly?

I'm making experiments with Fast RAM on EmuTOS. The amount of detected Fast RAM is always displayed on the EmuTOS welcome screen. So with WinUAE it is very easy to make tests: press F12, change the amount of Z3 RAM, reset, see the result... very handy.

Originally Posted by Toni Wilen

1: Simple "halve size of memory, try again and so on.." can be done. (instead of just setting memory size to zero)

Very good, thanks.

[Toni Wilen]

Originally Posted by BlankVector

I'm making experiments with Fast RAM on EmuTOS. The amount of detected Fast RAM is always displayed on the EmuTOS welcome screen. So with WinUAE it is very easy to make tests: press F12, change the amount of Z3 RAM, reset, see the result... very handy.

I hope you use autoconfig instead of poking around or there will be big surprises when using real Amigas..

UAE likes to put it at 0x10000000, AmigaOS on the other hand likes to start from 0x40000000 and there is some hackery to "move" it lower..

[BlankVector]

Originally Posted by Toni Wilen

I hope you use autoconfig instead of poking around

Of course.

I found the excellent Expansion implementation in AROS sources which perfectly fits my needs, no trouble there. It works perfectly for both Z2 and Z3 Fast RAM

Originally Posted by Toni Wilen

1: Simple "halve size of memory, try again and so on.." can be done. (instead of just setting memory size to zero)

I'm afraid I misunderstood this answer on my first read.
My initial complain was about the user not being informed when his settings are not respected. If your new code silently truncates down the configured RAM to some random value, it is not much better than 0.
The user must be informed about what is going on.

[Toni Wilen]

Originally Posted by BlankVector

The user must be informed about what is going on.

WinUAE never says anything (excluding possible logging) if there are configuration conflicts, it always have and always will silently "fix" them. Sorry.

Just check the log (or log console window) to see exactly right values.

[Toni Wilen]

Perhaps full Z3/MegaChip/RTG memory adjustment on the fly is possible after all.

Some rewriting needed to do before next beta. Of course it is also possible it can't be stable enough (for example it can cause other unexpected side-effects if "too much" virtual space is reserved on some Windows setups..)

(btw, Z3 changes only work accidentally, for example it totally breaks if RTG also changes..)