Improve Arma 3 Server Performance

This guide shows you how to optimize your Arma 3 server performance. Arma 3 is known for its high CPU usage – with these settings you'll get more stability and fewer lags.

Optimize hardware

• CPU: Arma 3 benefits massively from high single-core performance. A modern processor with high clock speed (4.0 GHz+) is more important than many cores. An i5 at 4.5 GHz clearly beats an old 16-core Xeon
• RAM: 8 GB minimum, 16 GB for servers with mods. Fast RAM (3200 MHz+) brings noticeable improvements
• Storage: Use NVMe SSD instead of HDD – mission files and mods load much faster

Optimize startup parameters

Add these parameters to your startup file:

-cpuCount=4 -exThreads=7 -high -maxMem=8192 -noLogs -enableHT

• -cpuCount=4: Number of physical cores the server should use
• -exThreads=7: Number of threads (always cpuCount * 2 - 1)
• -high: Sets server process to high priority in Windows
• -maxMem=8192: Maximum RAM in MB (8192 = 8 GB)
• -noLogs: Disables file logging – saves I/O and CPU
• -enableHT: Enables hyper-threading support

Optimize basic.cfg

These settings improve network performance and reduce bandwidth spikes:

MinBandwidth = 131072;
MaxBandwidth = 104857600;
MaxMsgSend = 256;
MaxSizeGuaranteed = 512;
MaxSizeNonguaranteed = 256;
MinErrorToSendNear = 0.029999999;
MinErrorToSend = 0.003;
MaxCustomFileSize = 0;

• MaxMsgSend: 256 instead of default 128 – more messages per frame possible
• MinErrorToSend: 0.003 instead of 0.01 – more frequent position updates, less warping
• MaxCustomFileSize: 0 disables size limit for custom files

Optimize server.cfg

verifySignatures = 0;
battleye = 1;
allowedFilePatching = 0;
kickDuplicate = 1;
loopCheck = 1;
equalModRequired = 0;
voteMissionPlayers = 1;
voteThreshold = 0.5;
maxPlayers = 32;
persistent = 1;

• verifySignatures = 0: Disables signature verification – less CPU load, but only recommended for private servers
• allowedFilePatching = 0: Prevents unauthorized changes to game files
• kickDuplicate = 1: Kicks duplicate connections – saves resources
• equalModRequired = 0: Allows players with fewer mods to join

Use headless clients

Headless clients distribute AI load across multiple processes. This is one of the most effective optimizations for Arma 3 servers with many AI units:

• Start one or more headless clients in addition to the main server
• Each headless client handles a portion of AI calculations
• Noticeably relieves the main server thread
• Especially effective for missions with 50+ AI units

Reduce AI count

• Fewer AI units = less CPU load. Reduce the number of simultaneous AI enemies
• Disable AI in areas where no players are present
• Use scripts that only spawn AI near players (e.g. DAC or ALICE)

Optimize mods

• Only install mods that are actually needed – each mod increases loading time and memory usage
• Large modpacks like RHS, CUP or ACE put heavy load on the server
• Regularly check mods for updates – outdated versions cause errors
• Optimize mod load order: Load dependencies first

Mission optimization

• Avoid too many objects on the map – every building and vehicle consumes resources
• Disable simulation for objects far away from players
• Use Dynamic Simulation – standard in newer missions
• Limit the number of simultaneously active scripts and triggers

Restart server regularly

• Daily restart prevents memory leaks – Arma 3 is known for this
• Use Windows Task Scheduler or cronjob for automatic restarts
• Always stop the server with #shutdown, don't close the window

Quick checklist

1. Choose CPU with high single-core performance, use NVMe SSD
2. Use startup parameters -cpuCount, -exThreads and -high
3. Adjust basic.cfg with optimized network values
4. Use headless clients for AI calculations
5. Reduce AI count, enable Dynamic Simulation
6. Deactivate unnecessary mods
7. Restart server daily