Phillz600 wrote:
i have this problem and it seems to be when iTunes is open, it's not just movies. At work i use Apple Music/iTunes on the MacBook for music between bands (I'm a sound engineer) sometimes I'll come home and forget iTunes is still open, then I'll play a game the next day or open safari and after about an hour, maybe less. I get the error 'Out of Application Memory'.
Do you have enough free disk space on the boot device so the operating system can create /var/vm/swapfile(s) for the virtual memory overflow?
If you have enough free disks space, then you have a process or collection of processes that are using more virtual memory than the operating system can manage (OS runs out of page table entries it can keep in RAM, and not take all of RAM just for page tables).
Generally this comes from either very memory hungry apps, especially if several are running concurrently, or from a process that has a memory leak.
Since this is the Mavericks forum, I can only assume you are running Mavericks, and there was a bug for a short time in Mail with attachments that experienced a memory leak. It was fixed, so if you are up-to-date with your Mavericks updates, that should not be the problem.
Applications -> Utilities -> Terminal
ps -ax -ovsz,comm | sort -k2n
will display the virual memory used in kilobytes by each process sorted least to most. That might help you find the worse virtual memory offenders.