How To Limit Memory Use


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. The RAM use will build up until you run out of memory. This can be fixed by starting the viewer from the command-line with the --memory-limit argument.

For instance, if you run rerun --memory-limit 16GB then the viewer will start throwing away the oldest logged so as not to go over that 16 GB limit.

NOTE: This currently only work when you are using rr.connect to connect to a separate rerun process. There is currently no way of specifying a memory limit when using rr.spawn.


If you have multiple processes generating log data to Rerun it could happen that the Viewer builds up a backlog of unprocessed log messages. This can induce latency and also use up memory, which --memory-limit cannot fix. To handle this case, you can use rerun --drop-at-latency 500ms to start ignoring new data if the input buffer exceeds 500ms of data.

This is a seldome used feature, and is mostly documented here for completeness.