multi processes

[garrickp at gmail.com]

On Feb 14, 7:53 am, "amadain" <mfmdev... at gmail.com> wrote:
> Hi
> Heres a poser. I want to start a program 4 times at exactly the same
> time (emulating 4 separate users starting up the same program). I am
> using pexpect to run the program from 4 separate locations accross the
> network. How do I start the programs running at exactly the same time?
> I want to time how long it takes each program to complete and to show
> if any of the program initiations failed. I also want to check for
> race conditions. The program that I am running is immaterial for this
> question - it could be mysql running queries on the same database for
> example. Using threading, you call start() to start each thread but if
> I call start on each instance in turn I am not starting
> simultaneously.
> A

Standard answers about starting anything at *exactly* the same time
aside, I would expect that the easiest answer would be to have a fifth
controlling program in communication with all four, which can then
send a start message over sockets to each of the agents at the same
time.

There are several programs out there which can already do this. One
example, Grinder, is designed for this very use (creating concurrent
users for a test). It's free, uses Jython as it's scripting language,
and even is capable of keeping track of your times for you. IMO, it's
worth checking out.

http://grinder.sourceforge.net