script

There are times when we want to see which threads are blocking our requests, and generating a thread dump is one way to find it out. The thing is sometimes we need to create a series of thread dumps, that’s why i have this script to do it for me. Create a file with the name of “jstack.sh”, with below script as its content

# number of cycles.
LOOP=3
# seconds between cycles.
INTERVAL=10

for ((i=1; i <= $LOOP; i++))
do
   _now=$(date)
   echo "\n \n ${_now}" >> cpu.out
   top -l 1 -o cpu -pid $1 >> cpu.out
   echo "\n \n ${_now}" >> tdump.out
   jstack -l $1 >> tdump.out
   echo "thread dump #" $i
   if [ $i -lt $LOOP ]; then
      echo "Sleeping..."
      sleep $INTERVAL
   fi
done

Repository for above script can be found below,

https://github.com/edwin/java-thread-dump