Following on to my post (make sure you read the comments if you want to do a project like this) at: https://k9zw.wordpress.com/2021/03/05/a-shack-resource-dissident-pi-project/
I’ve replaced the boot SD Card with a very inexpensive SSD drive and SATA to USB adapter.
The storage I/O improvement is stunning.
Winston KC9FVR tested and graphed the improvement. The axis is logarithmic which tends to visually understate the improvement. So yes, the SSD is about 70-times faster than the SD Card.
The running configuration is WorkPi with Dogfish SSD vs the supplied Patriot SD card or in the second graph a Thinkpad we had at hand.
The Raspberry Pi 400 that just arrived was also tested.
Winston KC9FVR caught that the inexpensive SATA to USB adapter disables the “Trim” in the attached SSD.
In simple form Trim is a SSD data management tool that offers much better performance than the automatic garbage collector basic SSD internal tool.
SSD manufacturers allow for a no-trim environment, and we have started a multi-month benchmarking project to see if this SSD starts to slow down.
Winston feels it will, where I am predicting no user discerned decline. Got a cup of coffee riding on the bet, so we will see!
Whether or not the adapter allows trim, the limiting factor is the USB.
Swapping in a better adapter and a gee-whiz ultra fast SSD will still be USB throughput limited in this application.