Performance Optimization

Learn how to maximize your file transfer speeds and optimize AirShare's performance.

Transfer Speed Basics

What Determines Speed?

Transfer speed depends on several factors:

1. Network type (Ethernet vs WiFi)
2. Network hardware (router, network cards)
3. Network congestion (other devices/apps)
4. Distance from router (WiFi only)
5. Interference (WiFi only)
6. Device performance (CPU, disk speed)

Expected Speeds

By Connection Type

By File Size

Small files (< 10 MB):

• Transfer mostly instant
• Overhead is noticeable
• Speed matters less

Medium files (10-500 MB):

• Speed becomes important
• Protocol overhead minimal
• Network is the bottleneck

Large files (> 500 MB):

• Speed is critical
• Use fastest connection possible
• Consider wired connection

Optimization Strategies

1. Use Wired Connection

Ethernet is always faster and more reliable than WiFi

Benefits:

• ✅ Consistent speed (no interference)
• ✅ Lower latency
• ✅ No signal degradation
• ✅ No WiFi congestion
• ✅ Better for large files

Recommendation: Use Gigabit Ethernet for both sender and receiver when transferring large files (> 1 GB).

2. Optimize WiFi

If you must use WiFi:

Use 5 GHz Instead of 2.4 GHz

5 GHz advantages:

• Faster speeds (2-5x)
• Less congestion
• More channels available
• Better for file transfers

2.4 GHz advantages:

• Better range
• Better wall penetration
• Use only if 5 GHz unavailable

How to switch:

1. Check if your router broadcasts both
2. Connect to the 5 GHz network (often has "5G" or "5GHz" in name)
3. Ensure both devices use 5 GHz

Position Devices Near Router

Signal strength matters:

• Close to router (< 10 feet): Maximum speed
• Same room (< 30 feet): Good speed
• Different room: Reduced speed
• Different floor: Significant reduction

Tip: Move closer to router for large transfers.

Minimize Interference

Sources of WiFi interference:

• ❌ Microwaves (especially 2.4 GHz)
• ❌ Bluetooth devices
• ❌ Cordless phones
• ❌ Baby monitors
• ❌ Other WiFi networks (neighbors)

Solutions:

• Turn off Bluetooth if not needed
• Change WiFi channel (router settings)
• Use 5 GHz (less interference)

Upgrade Router/WiFi Card

Old hardware = slow speeds:

Router:

• WiFi 4 (2010) → WiFi 5 (2013) → WiFi 6 (2019)
• Consider upgrading if router is > 5 years old
• WiFi 6 offers 2-3x speed increase

WiFi Card:

• Built-in WiFi may be old/slow
• USB WiFi adapters can upgrade (WiFi 6 recommended)
• Check your card's max speed in Device Manager/System Info

3. Reduce Network Congestion

Close bandwidth-heavy apps:

On both sender and receiver:

• ❌ Video streaming (Netflix, YouTube)
• ❌ Downloads/torrents
• ❌ Video calls (Zoom, Teams)
• ❌ Cloud sync (Dropbox, OneDrive, Google Drive)
• ❌ System updates
• ❌ Game downloads

Check bandwidth usage:

• Windows: Task Manager → Performance → Ethernet/WiFi
• macOS: Activity Monitor → Network
• Linux: iftop or nethogs

4. Optimize AirShare Settings

Transfer Buffer Size

Settings → Performance → Transfer Buffer Size

• Small (32 KB): For many small files
• Medium (64 KB): Default, balanced
• Large (128 KB): For files > 100 MB
• Huge (256 KB): For files > 1 GB on gigabit networks

Recommendation:

• Gigabit networks + large files: Huge
• WiFi or smaller files: Medium

Chunk Size

Settings → Performance → Chunk Size

• 1-2 MB: More protocol overhead, better error recovery
• 4 MB: Default, balanced
• 8-16 MB: Less overhead, faster for large files

Recommendation:

• Files > 1 GB on fast networks: 8-16 MB
• Standard use: 4 MB

TCP Congestion Control

Settings → Performance → TCP Congestion Control

• Enabled (default): Better on congested networks
• Disabled: Faster on fast, uncongested networks

Recommendation:

• Home network, gigabit: Disabled
• Shared/congested network: Enabled

Concurrent Transfers (Pro)

Settings → Performance → Maximum Concurrent Transfers

• 1: Queue mode (default)
• 2-5: Parallel transfers

Trade-off:

• More concurrent = more total throughput
• But each individual transfer is slower

Recommendation:

• Single large file: 1
• Many medium files: 3-5

5. Hardware Optimization

Use SSD Instead of HDD

Disk speed matters for large files:

SSD (Solid State Drive):

• Read/Write: 500-3,500 MB/s
• No bottleneck for network transfers

HDD (Hard Disk Drive):

• Read/Write: 80-160 MB/s
• Can bottleneck gigabit+ networks

Recommendation: Receive large files to SSD when possible.

Ensure Adequate CPU

AirShare uses CPU for:

• Encryption/decryption (TLS 1.3)
• Hash calculation (SHA-256)
• Data compression (if enabled)

Low-end CPUs may bottleneck at very high speeds (> 500 MB/s).

Check CPU usage during transfers:

• Should be < 30% on modern CPUs
• If 100%, CPU is bottleneck (rare)

Free Up RAM

Insufficient RAM can slow transfers:

• Minimum: 256 MB available
• Recommended: 512 MB available
• Large files (> 5 GB): 1 GB available

Check memory: Task Manager/Activity Monitor

6. Batch Transfers Efficiently

Group Files into Archives

For many small files:

Instead of: Transferring 1,000 individual files
Do: Zip/archive them first, transfer archive

Benefits:

• Faster (less protocol overhead)
• More reliable
• Easier to manage

Tools:

• Windows: Right-click → Send to → Compressed folder
• macOS: Right-click → Compress
• Linux: zip -r archive.zip folder/

Send Folders Instead of Files

AirShare is optimized for folder transfers:

• Maintains structure
• Single transfer operation
• Better progress tracking

Troubleshooting Slow Speeds

Speed Test Your Network

Test your local network speed:

Tools:

• iperf3: Network speed testing tool
• LAN Speed Test: Windows app
• Network Speed Tester: macOS/Linux

Example (iperf3):

# On receiver:
iperf3 -s

# On sender:
iperf3 -c RECEIVER_IP

# Should show your network's max speed

If iperf3 shows slow speeds, issue is network-related, not AirShare.

Compare WiFi vs Ethernet

Test both:

1. Transfer same file over WiFi → note speed
2. Transfer same file over Ethernet → note speed

If Ethernet is much faster: WiFi is the bottleneck
If both are slow: Check other factors

Check Transfer Speed Metric

AirShare shows real-time speed:

MB/s vs Mbps:

• AirShare shows MB/s (megabytes per second)
• Routers show Mbps (megabits per second)
• 1 MB/s = 8 Mbps

Example:

• Router: "450 Mbps WiFi"
• Expected AirShare speed: ~50 MB/s (450 ÷ 8)

Identify Bottleneck

Determine what's limiting speed:

1. Network: Most common (WiFi quality, congestion)
2. Disk: Old HDD can't keep up
3. CPU: Rare, but possible on very old computers
4. Other apps: Bandwidth hogs running

How to check:

• Transfer with everything closed → faster? = Other apps
• Transfer to different drive → faster? = Disk bottleneck
• Check CPU usage → 100%? = CPU bottleneck (very rare)
• Otherwise → Network bottleneck

Advanced Tips

Enable QoS on Router

Quality of Service (QoS) prioritizes traffic:

1. Access router admin panel
2. Find QoS settings
3. Prioritize AirShare ports: 59875-59925 UDP
4. Or prioritize by device MAC address

Benefit: AirShare gets priority over other traffic

Use Direct Connection

For absolute maximum speed:

1. Connect both devices directly with Ethernet cable
2. Configure static IPs on same subnet:
   • Device A: 192.168.2.1
   • Device B: 192.168.2.2
3. Launch AirShare on both
4. Should discover each other

Speed: Full Gigabit (100-125 MB/s) guaranteed

Disable Power Saving

Power saving can throttle network:

Windows:

1. Device Manager → Network Adapter
2. Properties → Power Management
3. Uncheck "Allow computer to turn off this device"

macOS:

1. System Settings → Energy
2. Disable "Low Power Mode"

Linux:

# Disable WiFi power saving
sudo iw dev wlan0 set power_save off

Update Network Drivers

Old drivers = slow speeds:

Windows:

1. Device Manager → Network Adapters
2. Right-click → Update Driver
3. Or download from manufacturer

macOS: Updates via System Updates

Linux:

# Check for driver updates via package manager
sudo apt update && sudo apt upgrade  # Debian/Ubuntu

Performance Benchmarks

Test Scenarios

Benchmark your setup:

Test 1: 100 MB file

• Expected (Gigabit): ~1 second
• Expected (WiFi 5): ~2-3 seconds

Test 2: 1 GB file

• Expected (Gigabit): ~8-10 seconds
• Expected (WiFi 5): ~20-40 seconds

Test 3: 10 GB file

• Expected (Gigabit): ~80-100 seconds
• Expected (WiFi 5): ~3-6 minutes

If your speeds are significantly slower, apply optimizations above.

Summary: Maximum Speed Checklist

Next Steps