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(bash) Script Processes in Parallel

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# 1  
Old 06-28-2018
(bash) Script Processes in Parallel
Hello all,

I tried to parralise my treatments but after a while 'ps -ef' display all child process <defunct> (zombie)

Parent bash script to process all files (>100000) in directory:

Code:
for filename in /Data/*.txt; do
   ./child_pprocess.sh $filename &
done

exit(0)

I understand that the parent process does not capture the end of each child process.

But I do not know how to do it.
does anyone have a suggestion ?

Thank you in advance
# 2  
Old 06-28-2018
You cannot create 100000 simultaneous child processes. Limit it to 20. And step through all of your files 20 at a time.

Code:
#/bin/bash   
cnt=0
for filename in /Data/*.txt; 
do
   ./child_pprocess.sh $filename &
    cnt=$(( $cnt + 1 ))
    if [ $(( $cnt % 20 )) -eq 0 ] ; then
       wait    # wait for all 20 to finish
    fi
done
wait   # you can get here with a few processes running, so wait for all of them

This User Gave Thanks to jim mcnamara For This Post:
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