a) it's 122GB free RAM (out of 128GB total RAM)

b) when I convert the numpy array to a list it works. So seems to be a problem with cPickle and numpy at/from a certain array size

c) $ /usr/bin/time -v python test_np.py 
Traceback (most recent call last):
  File "test_np.py", line 12, in <module>
    A2 = cPickle.load(f2)
MemoryError
Command exited with non-zero status 1
	Command being timed: "python test_np.py"
	User time (seconds): 73.72
	System time (seconds): 4.56
	Percent of CPU this job got: 87%
	Elapsed (wall clock) time (h:mm:ss or m:ss): 1:29.52
	Average shared text size (kbytes): 0
	Average unshared data size (kbytes): 0
	Average stack size (kbytes): 0
	Average total size (kbytes): 0
	Maximum resident set size (kbytes): 7402448
	Average resident set size (kbytes): 0
	Major (requiring I/O) page faults: 0
	Minor (reclaiming a frame) page faults: 726827
	Voluntary context switches: 41043
	Involuntary context switches: 7793
	Swaps: 0
	File system inputs: 3368
	File system outputs: 2180744
	Socket messages sent: 0
	Socket messages received: 0
	Signals delivered: 0
	Page size (bytes): 4096
	Exit status: 1

hth