How to interpret "failed to VM allocate" from Guard Malloc in Xcode

Is there a good tutorial on interpretation and problem-solving with Guard Malloc?

I'm getting message like "Failed to VM allocate 262144 bytes", and I have no idea what this means. Initially I thought it was the lack of RAM in the system, but maybe not so. If it is a problem I desperately need to learn how to interpret and catch the error.

Another question I have with Guard Malloc is whether it guards memory allocated in C codes of the project (it should right? considering the name) or only applying only to Objective-C? The reason I asked is that I just found out NSZombieEnabled only applies to Obj-C.

Help very much appreciated. I've been messing with likely memory errors for days. And I've not been able to compile Valgrind for iOS yet.