1 Reply Latest reply: Jun 18, 2013 10:39 AM by William Lloyd
William H. Magill1 Level 2 (200 points)

A particular 32 bit application which I run routinely has known memory leaks. That is not the question.


The question is about OSX Memory Management.


Simply put, why does OSX go into the "spinning bech ball" mode when a 32 bit application hits 3.7 GB of memory, insead of 4 GB?

(This is on an 8 GB iMac running 10.8.4)


OSX is clearly "protecting itself" in that only that application (and Activity Monitor if it is running)  are effected. Other apps continue to run normally.


If one attempts to Force quit the "spinning" app, it will take 30 - 45 minutes before it clears.

iMac, OS X Mountain Lion (10.8.2), iMac Core i7 2.93GHz 4GB
  • William Lloyd Level 7 (21,040 points)

    There is nothing special about 3.7 GB of memory versus 4 GB in Mountain Lion.  The OS is fully 64 bit and doesn't care one bit; it's just that the 32 bit application will see a 4 GB address space.


    It could be that there are other issues besides just a memory leak.  Perhaps the application has something that is blocking the main thread.  That is the main reason for the beachball: The main thread is blocked for some reason.  If you switch to another application does the beachball continue?