External Storage Guide

Recommended Configuration

Configuration	Recommended Value	Description
Capacity	256 GB or above	Depends on number of migrated apps
Interface	USB 3.0 or above / Thunderbolt	USB 2.0 is slow; large app migration takes longer
File System	APFS	Supports clones, snapshots, best performance

Interface Performance Comparison

Interface	Theoretical Speed	Actual Migration Speed	Use Case
USB 2.0	480 Mbps	~30 MB/s	Not recommended; too slow
USB 3.0 (USB-A)	5 Gbps	~350 MB/s	Basically sufficient
USB 3.1 Gen 2 (USB-C)	10 Gbps	~700 MB/s	Recommended
Thunderbolt 3/4	40 Gbps	~2500 MB/s	Best performance
NVMe (Thunderbolt)	40 Gbps	~2800 MB/s	Best performance

File System Recommendations

APFS (Recommended)

• Supports clones, snapshots, space sharing
• Best performance, especially for SSDs
• Native macOS support

HFS+

• Good compatibility; suitable for older Macs
• Does not support clones and snapshots
• Suitable for mechanical hard drives

exFAT

• Cross-platform compatible (macOS + Windows)
• Does not support hard links and clones
• Relatively lower performance
• Suitable for scenarios requiring use across multiple systems

Capacity Planning

AppPorts' external storage usage after migration depends on the size of migrated apps and data directories. Below are reference sizes for common apps:

App Type	Size
Chrome	~500 MB
Microsoft Office	~5 GB
Adobe Creative Cloud	~20-50 GB
Xcode	~15 GB
Final Cut Pro	~5 GB
Local large language models (Ollama)	~4-30 GB

💡 Capacity Recommendations

• Light use (5-10 apps): 128 GB
• Medium use (10-20 apps): 256 GB
• Heavy use (20+ apps + data directories): 512 GB or above

Notes

• External storage must remain connected; migrated apps and data directories cannot be used offline
• Regularly back up data on external storage
• Avoid unplugging external storage during migration
• If external storage fails, you can move apps back to local via AppPorts