Regarding your test results, I think the differences we are seeing in the builds is due to how we are building, both parameters and on what build platform, rather than the code changes I made. The code should either work or crash. It shouldn't have any impact on performance.
Which differences are you referring to? Running on PPC, there are no differences at all in behavior or performance between my March 2009 build and yesterday's build by you. There is a difference in audio performance with my July 2008 build, but many changes were added to CVS between July 2008 and March 2009 and, as I mentioned above, the July 2008 build was configured differently.
The performance difference on Intel is a real mystery. The one test we haven't tried is for someone else to do what I did: build on Leopard with the latest Xcode.
The difference is the difference in CPU usage. Apart from that, my builds with your code changes and your builds behave the same on my Intel machine. I did not yet build in Leopard. I will do that, the normal configuration on my iMac is 10.5.7 and XCode Tools 3.1.3. I did build with XCode 2.5 on Tiger to be sure the application would run in both Tiger and Leopard, but apparently that is not necessary.
It would also be interesting to know if building the PPC version on Leopard improves performance. I can't try it directly; I don't have any PPC machine running Leopard, and I don't have a retail install disk. I was thinking of trying to cross-compile, but this is tricky, since the config process itself compiles programs and runs them.
I lent one of my external drives to a friend. When I will have that drive back, I can install Leopard on it for my PowerBook G4.
It is strange to me that the PPC build has such terrible performance, since it runs natively. It should be just as fast as Classic. That's why we really need to figure out what is going on with the performance difference -- if we can solve it, maybe it will fix the PPC side too.
Performance on PPC has always been poor in all versions I used, starting with Gwenole's May 2006 snapshot. It never came even close to performance in Classic. Performance of SheepShaver on Intel has improved greatly since May 2006.
(The fact that my UB build is slow on PPC leads me to believe that does have to do with the version of Xcode tools; since like you, I built the PPC part on OS X 10.4)
See above. Your UB is not slower than previous builds. I built with XCode 2.5 that is designed to be used on both Tiger and Leopard.
Yes, the program changes are in code shared by all platforms, including Linux. For most platforms the net effect should be no change. But Linux and OS X share the same main code. So as far as I can tell, Linux should have had the same 512 MB limit, and with this code Linux will load the RAM/ROM anywhere.
Note that Linux can run on both PPC and Intel, so it has the same issues as OS X. As the code is right now, Linux on PPC can't move the ROM.
Anyway, Linux should be tested.
Right. No change can be added to CVS unless the result is OK for all configurations and platforms.