Migrating Pi 5 from microSD to USB3 Samsung 870 EVO SSD, and Pitfalls
Since I use Raspberry Pi 5 as a virtual machine (VM) host for Home Assistant OS (HAOS) in KVM, I want a system that is simple, stable, and reliable.
After repeated microSD drawbacks, I selected the Samsung 870 EVO SSD 500GB via USB3 over my previous Raspberry Pi 128GB microSD U2 for system storage.
Performance Comparison: microSD vs USB3 SSD
To quantify the improvement, I used:
curl https://raw.githubusercontent.com/TheRemote/PiBenchmarks/master/Storage.sh | sudo bash
Results
| Test | microSD Card | Samsung 870 EVO SSD | Improvement |
|---|---|---|---|
| HDParm Disk Read | 87.11 MB/sec | 362.74 MB/sec | 4.2x faster |
| HDParm Cached Disk Read | 83.74 MB/sec | 352.69 MB/sec | 4.2x faster |
| DD Disk Write | 71.0 MB/sec | 306 MB/sec | 4.3x faster |
| FIO 4k Random Read | 7,322 IOPS | 40,156 IOPS | 5.5x faster |
| FIO 4k Random Write | 4,070 IOPS | 35,679 IOPS | 8.8x faster |
| IOZone 4k Read | 22,064 KB/sec | 45,015 KB/sec | 2x faster |
| IOZone 4k Write | 10,453 KB/sec | 44,799 KB/sec | 4.3x faster |
| IOZone 4k Rand Read | 22,012 KB/sec | 23,832 KB/sec | 1.1x faster |
| IOZone 4k Rand Write | 14,664 KB/sec | 44,969 KB/sec | 3.1x faster |
| Overall PiBenchmarks Score | 4098 | 14655 | +3.6x higher |
Summary:
The USB3 SSD is consistently at least 4x faster for sequential reads/writes, and up to 9x faster for random IO operations. This means faster boot times, quicker VM performance, and far more reliability for Home Assistant and other hosted services.