psutil module not fully working on debian 7

Question

I'm trying to get the amount of free memory in the system using python. basically the same info that i can get from cat /proc/meminfo | grep MemFree cat /proc/meminfo | grep MemFree .

>>> import psutil
>>> psutil.NUM_CPUS # this works fine
2
>>> psutil.virtual_memory() # this fails
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'virtual_memory'

i'm using python 2.7.3

update

>>> psutil.__version__
'0.5.0'

Answer 1

Python 2.7.5+ (default, Sep 19 2013, 13:48:49) 
[GCC 4.8.1] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import psutil
>>> psutil.NUM_CPUS # this works fine
4
>>> psutil.virtual_memory() # this fails
vmem(total=4042084352L, available=1697619968L, percent=58.0, used=3149373440L, free=892710912L, active=2016649216, inactive=835248128, buffers=55672832L, cached=749236224)
>>> quit()
~$ cat /proc/meminfo | grep MemFree
MemFree:          876836 kB
~$ python -c "print 892710912/1024"
871788
~$ python -c "import psutil;print psutil.__version__"
1.1.3

Possibly you need to run:

sudo pip install psutil --upgrade

Note that you will never get exactly the same answers as you are running python in one case and not in the other.