ZZ: When Linux Runs Out of Memory (OOM killer)

When Linux Runs Out of Memory
http://linuxdevcenter.com/pub/a/linux/2006/11/30/linux-out-of-memory.html?page=1
Perhaps you rarely face it, but once you do, you surely know what's
wrong: lack of free memory, or Out of Memory (OOM). The results are
typical: you can no longer allocate more memory and the kernel kills a
task (usually the current running one). Heavy swapping usually
accompanies this situation, so both screen and disk activity reflect
this.
At the bottom of this problem lie other questions: how much memory
do you want to allocate? How much does the operating system (OS)
allocate for you? The basic reason of OOM is simple: you've asked for
more than the available virtual memory space. I say "virtual" because
RAM isn't the only place counted as free memory; any swap areas apply.
Exploring OOM