Multiple python script faster in different sessions?

[supernoob]

Hi all,
I've developed three python modules that I usually run with:

Code: Select all

sudo python process1.py &
sudo python process2.py &
sudo python process3.py &

Three python modules makes operation over two different xml files.

If I run all of them in the same session (for example through a .sh script or starting them manually)  seems that elaboration time is about a 30% more (slower).
If I run all of them in separate sessions all seems to be faster.

Questions:
1 - why is this happening ?
2 - how I could automatically run (after boot) these three script in three separate sections ?

Thanks very much,
regards to all.

SuperNoob

[elatllat]

use 'time' to get some real numbers, then to it 10 more times to see if it's consistant.
use nice if you want to give one priority
read about scheduling: http://en.wikipedia.org/wiki/Scheduling ... nux_2.6.23
use init.d to run after boot.
use screen or tmux or nohup and check printenv to use different sessions


more swapping between tasks will slow things down... why are you running these in parallel?
it would probably be faster and definitely less memory intensive if you did your parallelism in python.