Hi overthere

I know that there's more to it , the OS can't boot off the "hIOmon software" and the hIOmon software can't be the first service to start.
I expect that the bootup metrics would generally be misleading when comparing installs across different computers.
It should be consistent for that exact pc/install though. (still there will be activities that are not captured/monitored due to the nature of booting)

Booting is not what brought me to trying the software though.
It does bring quite a lot of interesting points to the table (also while booting), like QD, comparing: seq. Vs random io, pagefile vs no pagefile, single drives vs raid and I would expect for determining optimal strip sizes.

I've found hIOmon to be a great tool for capturing/monitoring tasks.

I'll be comparing i/o on VMs on both HDDs and SSDs on different controllers this weekend, should be interesting and probably very time consuming

Regarding my HDD vs SSD bootup metrics
The F3 boots in about 21-22 seconds (using boottimer) and so the period to monitor could easily have been set to 60 seconds (or less), I don't think that would have changed anything, that is unless there were some random scheduled activities that started during the monitoring period. (i.e. windows update, AV scan, ...)
Like you've already mentioned, it's all down to when the monitoring starts.
Both the SSD and the HDD are capable of reading/writing TBs of data during the 2 minute monitoring period so that's a moot point wrt to comparing total i/o during bootup.
Looking at the idle/busy time percentages confirms that most of the time it's just idling during the 2 minute period.
(and that the idle part is in favour of the SSDs )