Here’s a bash script called realtime.sh that switches your game servers to realtime mode. It significantly improves the overall stability of HLDS/SRCDS-based servers, including:

• Counter-Strike
• Left 4 Dead
• Day of Defeat
• Team Fortress

✅ Fully compatible with Counter-Strike: Global Offensive and Counter-Strike 2.

🔧 What does this script do?

The realtime.sh script leverages the Linux realtime scheduling system to assign higher CPU priority to critical processes — like your game servers.

• Detects running server processes (e.g., srcds_linux, cs2, etc.)
• Applies realtime priority using chrt -f -p
• Also optimizes internal kernel timer processes

🎯 Result: the OS gives your game server top CPU priority, reducing latency and micro-lags.

📈 Does it increase FPS?

Indirectly, yes. This script doesn’t generate more FPS, but it stabilizes the frame rate and reduces OS multitasking slowdowns.
➕ Less fluctuation ➝ Smoother experience ➝ Happier players.

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⚙️ Installation & usage

1. Create the file:

   nano /home/realtime.sh

2. Paste in the following content:

   #!/bin/sh
   PROCESS_NAMES="srcds_linux srcds_i686 srcds_i486 srcds_amd hlds_i686 hlds_i486 hlds_amd cs2"
   for name in $PROCESS_NAMES; do
   PIDS=$(pidof $name)
   for p in $PIDS; do
   chrt -f -p 98 $p
   done
   done
   # Optimisation supplémentaire pour noyaux RT
   PIDS=$(ps ax | grep sirq-hrtimer | grep -v grep | awk '{print $1}')
   for p in $PIDS; do
   chrt -f -p 99 $p
   done
   PIDS=$(ps ax | grep sirq-timer | grep -v grep | awk '{print $1}')
   for p in $PIDS; do
   chrt -f -p 51 $p
   done

3. Make it executable:

   chmod 755 /home/realtime.sh

4. Add it to cron to run every 5 minutes:

   sudo nano /etc/crontab

   Append this line:

   */5 * * * * root /home/realtime.sh > /dev/null 2>&1

✅ That’s it! Your servers will now run with higher scheduling priority automatically.

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⏱️ Bonus tip: change the system clock source

Linux uses a system clocksource for timing. By default, it’s usually tsc, which can be unstable on some CPUs.
You can test a more stable source like hpet or acpi_pm:

• Show available clock sources:

  cat /sys/devices/system/clocksource/clocksource0/available_clocksource

• See the current clock source:

  cat /sys/devices/system/clocksource/clocksource0/current_clocksource

• Temporarily switch to hpet:

  echo hpet | sudo tee /sys/devices/system/clocksource/clocksource0/current_clocksource

ℹ️ This change is temporary and will reset after reboot. For a permanent change, edit your GRUB boot line.

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🎉 Congratulations! You’ve taken a major step toward a more stable and professional game server. Don’t hesitate to share this tip with fellow admins to improve multiplayer experiences.

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- ✍️ Written on: 26/06/2025 à 20h00
- 🔄 Last updated on: 26/06/2025 à 20h00
- 🧠 Author: Slymer  | Idée originale par : BehaartesEtwas
- 💬 Community discussion: View the conversation