script to sync producer consumer application.

ufmale · 06-08-2010, 01:32 AM

I have a producer and consumer application, each can take parameter
and run for 10 minutes.

I want to write a script that allow me to pass in different paramters
and save the results for later. However, I cannot come up with a write
script.

Can someone suggest a good approach or any tool that can help?

My scenario is that the consumer has to start first always.
Once the first set of parameter finish. the producer will not start
until the consumer for the next parameter set starts
I am thinking something like this

Consumer:

for ($i=1;$i<10;$i++)
startconsumer.sh -interval $i
sleep 1
end

Producer:
for ($i=1;$i<10;$i++)
startproducer.sh -interval $i
# wait till consumer is done
sleep 1;
end

I am trying to go with an approach that checking if the consumer/producer finish by checking a log file, but it does not seem to work.

Maybe someone has done something similar already

timmeke · 06-08-2010, 01:51 AM

One approach to check for running apps would be to use "PID files" in /var/run, like daemons do. In these files, the daemon logs it's process ID (PID) number when it starts up (and clears/removes the file when it finishes).

Quote:

My scenario is that the consumer has to start first always.
Once the first set of parameter finish. the producer will not start
until the consumer for the next parameter set starts

After reading your scenario, though, I'm not sure that it's a daemon like approach that you want.
How about this approach:

Code:

startconsumer.sh; #run once, wait for consumer to finish - first consumer
for ($i=1;$i<10;$i++); do
startproducer.sh &; #no need to wait
startconsumer.sh; #wait till completed
done;

In the first iteration, the producer will start just after the first consumer finished.
A sleep time between producer & consumer can help make sure that the producer is done roughly by the
time that the repeated consumer is done as well.

A while-loop can be more suitable for this.

theNbomr · 06-08-2010, 09:55 AM

Your problem is that of synchronization. In your script, you have the comment '# wait till consumer is done'. How will your producer process know that the consumer is done? And the flip-side question is, how does the producer know that a new consumer process is ready? Once you've answered these questions, I think you will have the solution.
--- rod.