Parallel Execution

Shell Programming and Scripting
1

Hello,

I wish to run parallel process forked from one script.
Currently I doing is submit them in background.

For example:
---------------------------------------------------------------
#!/usr/bin/ksh

process1 &
process2 &
process3 &
.....
.....

#here I check for completion of all process success.
#each process writes its status to a file
while true
do
# code to check success

done
---------------------------------------------------------------

Is there a better way to execute jobs in paralle?
If yes please advise.

Thanks,
Rishi

2

Assuming that by running separate processes you get better throughput, this is a fine way to proceed.

3

What about something like...

#!/bin/ksh

./a.sh &
pid_a=$!
./b.sh &
pid_b=$!
./c.sh &
pid_c=$!

wait $pid_a
echo "a.sh returned $?"
wait $pid_b
echo "b.sh returned $?"
wait $pid_c
echo "c.sh returned $?"

-Om

4

it can be good replacement if I was not seeking parallel execution...
I believe with wait the execution will become sequential...and waiting for all the process finishing starting from one...

my requirement is suppose one process is finished I need to start some processing on data prepared by tht process....

in this case say process a takes largest time then I need to wait till process a to finish before I begin for processing of b,c...z though they have already finished...

Rishi

5

RishiPahuja -

We use the control file method just like you do. Sorry for any confusion