chore: high memory usage debugging script [skip ci]

scripts/mysql_highmem_watcher.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+POLL_INTERVAL=1  # sec
+MEMORY_THRESHOLD=1024  # MB
+TARGET_PROCESS_NAME="wakapi/wakapi"  # process under suspicion
+
+# MySQL credentials
+MYSQL_USER="wakapi"
+MYSQL_PASSWORD="sshhhh"
+MYSQL_HOST="127.0.01"
+MYSQL_PORT="3306"
+
+OUTPUT_DIR="/tmp"
+
+check_free_memory() {
+    FREE_MEMORY=$(free -m | awk 'NR==2{printf "%.2f\n", $7}')
+    # echo "Free Memory: $FREE_MEMORY MB"
+    if (( $(echo "$FREE_MEMORY < $MEMORY_THRESHOLD" | bc -l) )); then
+        TARGET_PROCESS_MEM=$(ps aux | grep "$TARGET_PROCESS_NAME" | grep -v "grep" | awk '{print $6}')
+        echo "[$(date)] Available memory dropped below threshold. Is now $FREE_MEMORY. Suspicious process uses $TARGET_PROCESS_MEM bytes. Dumping MySQL process list ..."
+        dump_mysql_processlist
+        create_heap_dump
+    fi
+}
+
+dump_mysql_processlist() {
+    TIMESTAMP=$(date +"%Y%m%d_%H%M%S")
+    OUTPUT_FILE="$OUTPUT_DIR/mysql_processlist_$TIMESTAMP.txt"
+    mysql -u $MYSQL_USER -p$MYSQL_PASSWORD -h $MYSQL_HOST -P $MYSQL_PORT -e "SHOW PROCESSLIST;" > $OUTPUT_FILE
+    echo "[$(date)] Saved to $OUTPUT_FILE"
+}
+
+create_heap_dump() {
+    TIMESTAMP=$(date +"%Y%m%d_%H%M%S")
+    OUTPUT_FILE_1="$OUTPUT_DIR/heap_inuse_$TIMESTAMP.svg"
+    OUTPUT_FILE_2="$OUTPUT_DIR/heap_alloc_$TIMESTAMP.svg"
+    go tool pprof -inuse_space -svg http://localhost:6060/debug/pprof/heap > "$OUTPUT_FILE_1"
+    go tool pprof -alloc_space -svg http://localhost:6060/debug/pprof/heap > "$OUTPUT_FILE_2"
+    echo "[$(date)] Saved heap graph to $OUTPUT_FILE"
+}
+
+while true; do
+    check_free_memory
+    sleep $POLL_INTERVAL
+done