From 98cb879ee1872d8d9f88a1a57a31876ad71dc3db Mon Sep 17 00:00:00 2001
From: Renz <renz@uuxo.net>
Date: Fri, 14 Nov 2025 08:34:16 +0000
Subject: [PATCH] Add BLOB/large object verification script for backup
 diagnostics

---
 fix_max_locks.sh | 49 ++++++++++++++++++++++++++++--------------------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/fix_max_locks.sh b/fix_max_locks.sh
index 5bf3c9e..2e9ea86 100755
--- a/fix_max_locks.sh
+++ b/fix_max_locks.sh
@@ -6,44 +6,53 @@
 set -euo pipefail
 NEW_VALUE=${1:-256}
 
-CONFIG_FILE="$(sudo -u postgres psql -t -c "SHOW config_file;" | tr -d '[:space:]')"
-if [ -z "$CONFIG_FILE" ]; then
-  echo "Could not locate postgresql.conf; aborting"
-  exit 1
-fi
-
-echo "postgres config file: $CONFIG_FILE"
+CONFIG_FILE="/var/lib/pgsql/data/postgresql.conf"
 BACKUP_FILE="${CONFIG_FILE}.bak.$(date +%s)"
 
+echo "PostgreSQL config file: $CONFIG_FILE"
+
 # Create a backup
 sudo cp "$CONFIG_FILE" "$BACKUP_FILE"
-sudo chown postgres:postgres "$BACKUP_FILE"
-chmod 600 "$BACKUP_FILE"
-
 echo "Backup written to $BACKUP_FILE"
 
-# Use sed to update (or add) setting
-# If the setting is present (commented or uncommented), replace the line. Otherwise append.
-if sudo grep -q "^\s*max_locks_per_transaction\s*=\s*" "$CONFIG_FILE"; then
+# Check if setting exists (commented or not)
+if sudo grep -qE "^\s*#?\s*max_locks_per_transaction\s*=" "$CONFIG_FILE"; then
   echo "Updating existing max_locks_per_transaction to $NEW_VALUE"
-  sudo sed -ri "s#^\s*#?max_locks_per_transaction\s*=.*#max_locks_per_transaction = $NEW_VALUE#" "$CONFIG_FILE"
+  # Replace the line (whether commented or not)
+  sudo sed -i "s/^\s*#\?\s*max_locks_per_transaction\s*=.*/max_locks_per_transaction = $NEW_VALUE/" "$CONFIG_FILE"
 else
   echo "Adding max_locks_per_transaction = $NEW_VALUE to config"
-  echo "\n# Increased by fix_max_locks.sh on $(date)\nmax_locks_per_transaction = $NEW_VALUE" | sudo tee -a "$CONFIG_FILE" >/dev/null
+  # Append at the end
+  echo "" | sudo tee -a "$CONFIG_FILE" >/dev/null
+  echo "# Increased by fix_max_locks.sh on $(date)" | sudo tee -a "$CONFIG_FILE" >/dev/null
+  echo "max_locks_per_transaction = $NEW_VALUE" | sudo tee -a "$CONFIG_FILE" >/dev/null
 fi
 
 # Ensure correct permissions
 sudo chown postgres:postgres "$CONFIG_FILE"
 sudo chmod 600 "$CONFIG_FILE"
 
+# Test the config before restarting
+echo "Testing PostgreSQL config..."
+sudo -u postgres /usr/bin/postgres -D /var/lib/pgsql/data -C max_locks_per_transaction 2>&1 | head -5
+
 # Restart PostgreSQL and verify
 echo "Restarting PostgreSQL service..."
 sudo systemctl restart postgresql
-sleep 2
+sleep 3
 
-echo "Verifying new value:"
-sudo -u postgres psql -c "SHOW max_locks_per_transaction;"
-
-echo "If the restart fails, you can restore the previous config with:\n  sudo cp $BACKUP_FILE $CONFIG_FILE && sudo systemctl restart postgresql"
+if sudo systemctl is-active --quiet postgresql; then
+  echo "✅ PostgreSQL restarted successfully"
+  sudo -u postgres psql -c "SHOW max_locks_per_transaction;"
+else
+  echo "❌ PostgreSQL failed to start!"
+  echo "Restoring backup..."
+  sudo cp "$BACKUP_FILE" "$CONFIG_FILE"
+  sudo systemctl start postgresql
+  echo "Original config restored. Check /var/log/postgresql for errors."
+  exit 1
+fi
 
+echo ""
+echo "Success! Backup available at: $BACKUP_FILE"
 exit 0