memory per process/core

[Duke Nguyen]

Hi folks,

We have SL6.3 64bit installed on a box with two quad core and 8GB RAM. 
We installed openmpi, Intel Studio XE and abinit to run parallel (8 
cores/processes) some of our applications. To our surprise, the system 
usually takes only about half of available memory (about 500MB each 
core) and then the job/task was killed with the low-resource error.

We dont really understand why there is a cap of "512MB" (I guess it 
would be 512MB instead of 500MB) for each of our cores whereas in 
theory, each of the core should be able to run up to 1GB. Any 
suggestions/comments/experience about this issue?

Thanks in advance,

D.