We are having a few lag spikes where ticks randomly take several seconds. It is rare enough that it doesn't really show anything in particular on the general monitoring report. It would be nice to be able get a breakdown of everything that happened during that specific tick.

/spark start --only-ticks-over <lag spike length in ms>

Ah, and the resulting report will only contain measurements from those specific ticks?

Oh, wait I was thinking of the monitoring command, nvm, yes that's great thanks.

(you can close the issue if your issue is resolved)

More info can be found here:
https://github.com/lucko/spark/wiki/Finding-the-cause-of-lag-spikes

Thank you very much!