Running MacOS 8.5.1 without VM, I noticed that the MacOS memory partition jumps 13Mb when we launch a recent debug build of AppRunner. After some verifications, it doesn't seem to be related to the offscreen graphics. I suspect that we are loading the shared libs in the system heap. Does someone know whether it is the case? And is it a good thing to do?

Nothing has changed with library loading. Did you just turn VM off?

Note also that the default partition is 12037k. I think jj changed this a while back.

I always have VM off but I only noticed the problem today. I don't think it is the offscreen buffers because: - The "About This Computer" dialog in recent versions of the MacOS show the offscreen buffers usage under the application's partition, not under the OS partition. - GFX allocates the offscreen buffers in the app heap first and then in the system heap so I ran the application within a partition of 40Mb (then with plenty of unused space) and the MacOS partition was still jumping 13Mb. I highly suspect the shared libs because: - I was able the app within a 6Mb partition, which should have been really insufficient and which even used to crash, letting me think that something had change in the way we load the components. - I think I saw a little while ago that the size of our debug shared libs was more than 10Mb.

I think that with VM off, the OS is loading code fragments into the system heap (or at least space that gets lumped in with 'Mac OS' in the About this Mac' window; it might be using temp mem). There is good reason for this. The system adjusts your application heap size when VM is off to take into account the size of the code, but it only knows about the size of the code in the app's data fork. So it increased the assigned heap space by that amount. Subsequent library loads don't go into the app's heap, because the OS has know way of knowing how large they will be. So I think you're just seeing loaded code size. I see 4.5 increasing Mac OS usage by about 4MB in the same way.

Ok, closing as Invalid.

Rubber-stamping as verified, under SIAR principle. (aka Simon Is Always Right. ;)