Something wrong with memory calculation.

[bga]

This bug becomes evident when allocating a big chunk of memory in one go. Activity Monitor will report a negative amount of used memory. This does not seem to be an Activity Monitor problem as even sysinfo acts in a weird way.

This is what I got before allocating 500 Mb in one go (snippet form sysinfo output):

2013855744 bytes free (used/max 133627904 / 2147483648)

(cached 17035264)

And with the memory allocated:

1397829632 bytes free (used/max 749654016 / 2147483648)

(cached 3696230400)

The values for used memory and cache do not look right.

[anevilyak]

Used memory actually looks like it's in the correct ballpark for an additional 500MB alloc. The fact that the numbers there look more or less sane though makes me suspect vm_page_num_free_pages() is returning the wrong value here, but that implies several possible variables as suspects. Possibly sInactivePageQueue?

[bonefish]

Should be fixed in hrev26837. Note that a huge allocation won't show up, unless it is fully locked or until the memory is touched. The values now reported by get_system_info() reflect the actual page usage instead of the memory commitment. It wouldn't be too difficult to change that, if the general preference is otherwise. I haven't tested what BeOS does.

[axeld]

I like it as is; that just makes more sense to me.