1  #!/bin/bash
 2  #
 3  # Dashboard Health Monitor
 4  # Checks if dashboard is running on port 8501 and relaunches if down
 5  # Runs with lowest priority (nice 19, ionice idle class)
 6  #
 7  
 8  set -euo pipefail
 9  
10  # Check if port 8501 is in use
11  if ss -tlnp | grep -q ":8501" >/dev/null 2>&1; then
12      echo "Dashboard is running on port 8501"
13      exit 0
14  fi
15  
16  echo "Dashboard not detected on port 8501, relaunching..."
17  
18  # Change to project directory
19  cd "$(dirname "$0")/.." || exit 1
20  
21  # Launch dashboard with lowest priority
22  # nice 19 = lowest CPU priority
23  # ionice -c 3 = idle I/O priority (only when no other I/O) - optional
24  if command -v ionice >/dev/null 2>&1; then
25      nohup nice -n 19 ionice -c 3 npm run dashboard \
26          >/dev/null 2>&1 &
27  else
28      nohup nice -n 19 npm run dashboard \
29          >/dev/null 2>&1 &
30  fi
31  
32  # Wait a moment and verify it started
33  sleep 3
34  
35  if ss -tlnp | grep -q ":8501" >/dev/null 2>&1; then
36      echo "Dashboard successfully relaunched"
37      exit 0
38  else
39      echo "WARNING: Dashboard not available - will retry next cycle (non-critical)"
40      exit 0
41  fi