Limit the viewer's memory usage
--memory-limit
The Rerun Viewer can not yet view more data than fits in RAM. The more data you log, the more RAM the Rerun Viewer will use. When it reaches a certain limit, the oldest data will be dropped. The default limit it to use up to 75% of the total system RAM.
You can set the limit by with the --memory-limit command-lint argument, or the memory_limit argument of rr.spawn.