spring-boot-demo-oom: five real memory-leak demos with captured OOM + MAT evidence

2026-10-01 12:11:56 +00:00
commit fd035a79e8
41 changed files with 1317 additions and 0 deletions
@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+# Runs docs/output/heap.hprof (produced by scripts/run.sh) through Eclipse Memory Analyzer's
+# headless batch report generator -- MemoryAnalyzer's -application org.eclipse.mat.api.parse,
+# invoked via the ParseHeapDump.sh wrapper MAT ships -- then re-extracts the Problem Suspect
+# summary into docs/output/02-mat-leak-suspects.txt.
+#
+# No GUI is shown, but MAT's SWT runtime still needs an X display even in this mode, hence
+# xvfb-run. Needs: MAT_HOME pointing at an extracted Memory Analyzer 1.17.0+ "rcp" distribution,
+# and xvfb-run on PATH (package "xvfb" on Debian/Ubuntu).
+set -eu
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+MODULE_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+ROOT_DIR="$(cd "$MODULE_DIR/.." && pwd)"
+cd "$MODULE_DIR"
+
+: "${MAT_HOME:?Set MAT_HOME to your Memory Analyzer install (e.g. /opt/mat)}"
+if [ ! -f docs/output/heap.hprof ]; then
+  echo "docs/output/heap.hprof not found -- run scripts/run.sh first" >&2
+  exit 1
+fi
+rm -f docs/output/heap_Leak_Suspects.zip
+xvfb-run -a "$MAT_HOME/ParseHeapDump.sh" "$MODULE_DIR/docs/output/heap.hprof" org.eclipse.mat.api:suspects
+python3 "$ROOT_DIR/scripts/extract-mat-summary.py" "$MODULE_DIR"
@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+# Drives threadlocal-leak to a REAL java.lang.OutOfMemoryError under a constrained heap, with
+# -XX:+HeapDumpOnOutOfMemoryError so the crash leaves a real .hprof behind. Also regenerates
+# docs/output/01-oom-console.txt from the real run log.
+#
+# Needs JDK 25 (LTS) on PATH.
+set -eu
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+MODULE_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+ROOT_DIR="$(cd "$MODULE_DIR/.." && pwd)"
+cd "$MODULE_DIR"
+
+mvn -q -B package -DskipTests
+mkdir -p docs/output
+rm -f docs/output/heap.hprof
+CMD="java -Xmx220m -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=docs/output/heap.hprof -jar target/threadlocal-leak.jar"
+echo "== running: $CMD =="
+LOG="$(mktemp)"
+$CMD > "$LOG" 2>&1 || true
+python3 "$ROOT_DIR/scripts/extract-oom-console.py" "$MODULE_DIR" "$LOG" "$CMD"
+rm -f "$LOG"
+echo "heap dump: docs/output/heap.hprof (not committed -- see .gitignore; regenerate it with this script)"