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Performance — MB/s better than microseconds

#1

Tom-Ottawa

Tom-Ottawa

It would be more useful to display the transfer speed in MB/second. Microseconds? Is that for a 1kb read/write or 4GB?
In other words, better to display the performance of the drive rather than the performance of Validrive.


#2

Steve

Steve

@Tom-Ottawa:

The reason I don't for ValiDrive v1.x is that ValiDrive's rapid back and forth switching between reading and writing is actually measuring the drive's worse-case "switching" performance rather than its transfer speed. Writing to NAND flash media requires the generation of a high internal voltage which is used to break through (tunnel electrons) an insulation boundary. And reading requires that voltage to be dumped. The generation of that high voltage takes time (to pump up)... So there's nothing more time consuming than switching back and forth between reading and writing as ValiDrive does. This means that it's really not a fair measure of performance.

Having learned many lessons from this first ValiDrive v1.x release, I plan to take a bit of time once SpinRite v6.1 is published to update it to v2.0, which will (a) run MUCH faster and (b) produce some more useful metrics. (y)


#3

Steve

Steve

There's quite a few factors affecting write speed and all operations require "charge pumping" and they're usually measured in us (microseconds).
I suspect that ValiDrive v2.0 will teach us quite a lot. (y)