#!/usr/bin/env bash
# Runs each approach against the huge file under a ladder of -Xmx limits, one fresh JVM per run.
# Streaming modes run every rung (to show memory stays flat). Tree/bind climb until the first
# rung that succeeds, then stop. Output: output/bench.txt   (timings vary run to run)
set -u
cd "$(dirname "$0")/.."
FILE="${1:-target/huge.json}"
CP="target/classes:$(cat target/cp.txt)"
OUT=output/bench.txt
mkdir -p output
{
  echo "file: $FILE ($(stat -c %s "$FILE") bytes)"
  echo "java: $(java -version 2>&1 | grep -v 'Picked up' | head -1)"
  echo "cpus: $(nproc)   ram: $(free -m | awk '/Mem:/{print $2}') MB"
  echo
  for mode in stream hybrid; do
    for x in 32 64 128 1024; do
      java -Xmx${x}m -cp "$CP" com.ankurm.jackson3.streaminghuge.Scan $mode "$FILE" 2>&1 | grep -v '^Picked up'
    done
  done
  for mode in tree bind; do
    for x in 64 256 1024 2048 3072 4096 6144; do
      line=$(timeout 900 java -Xmx${x}m -cp "$CP" com.ankurm.jackson3.streaminghuge.Scan $mode "$FILE" 2>&1 | grep -v '^Picked up'; echo "exit=${PIPESTATUS[0]}")
      # no output at all = the JVM was SIGKILLed (exit 137) by the container's OOM killer
      case "$line" in exit=*) line=$(printf '%-7s -Xmx=%5d MB  KILLED  no Java output, %s (SIGKILL by the OS: the heap limit was larger than free RAM)' "$mode" "$x" "$line");; *) line="${line%exit=*}"; line="${line%$'\n'}";; esac
      echo "$line"
      case "$line" in *" OK "*) break;; esac
    done
  done
} | tee "$OUT"