Am a newbie to Tempo and was also searching for the same.
Like you couldn’t find none. Let me know if you happened to find something.
Any how a few info that I came across and see if it helps.
- Traces/Spans per second
- Size of Trace/Span
- ingester flush period
- This discussion in this forum , you may find interesting .(Tempo ram usage for 6k spans per hour)