Free up memory on Mac OS X

Here is another tip how to free up memory (last weeks tip was on freeing up memory on Ubuntu).

I’ve a MacBook Pro with 8GB RAM and unfortunately constantly battle with memory usage. That is, I’ve got Tomcat, OpenBD, MySQL, MongoDB, Sublime Text 2, FireFox, Safari, BBEdit, Terminal, SQL Editor, Source Tree, iTunes, Skype and some other small tools constantly running. Now, from time to time it happens that just about all RAM is eaten up (especially by Firefox (yes, still after all these years they haven’t managed to get this issue fixed)).

Fortunately there is the “purge” command that forces disk and memory caches to be emptied, offering a “cold disk buffer cache” which is similar to the state of the operating system after a reboot. Simply enter the “purge” command in your terminal window. Open up the “Activity Monitor” and after a while you should see a massive recovery of your RAM (mine just went from Free:100MB to Free:4.70GB).

Note: You may need to have the Developer Tools installed in order to use the purge command.