gen.sh

#!/bin/bash

# Usage: ./gen.sh collected-stacks.txt

TMPSTACKS=/tmp/flamegraph-stacks-collapsed.txt
TMPPALETTE=/tmp/flamegraph-palette.map

./stackcollapse-jstack.pl $1 > $TMPSTACKS

# 1st run - hot: default
./flamegraph.pl --cp $TMPSTACKS > stacks.svg

# 2nd run - blue: I/O
cp palette.map $TMPPALETTE
cat $TMPPALETTE | grep -v '\.read' | grep -v '\.write' | grep -v 'socketRead' | grep -v 'socketWrite' | grep -v 'socketAccept' > palette.map
./flamegraph.pl --cp --colors=io $TMPSTACKS > stacks.svg

echo "Done! Now see the output in stacks.svg"

profile.sh

#!/bin/sh

# Usage: ./profile.sh pid output.txt

PROFILED_PID=$1
OUTPUT_FILE=$2

echo "Getting stacktraces from process $PROFILED_PID... Will stop on ^C or when the process exits."

rm -f "$OUTPUT_FILE"

while true; do
    jstack "$PROFILED_PID" >> "$OUTPUT_FILE" && sleep 0.01 || break
done

echo
echo "Done! Stacks saved to $OUTPUT_FILE"