Lag¶
For identifying Lag sources/causes most of our packs have Spark and Observable in them by Default.
Spark Profiler¶
Normal players also have access to the command /spark tps & /forge tps and that gives a general indication of any potential lag issues that might need investigating.
For Spark, players in SP worlds with cheats enabled, or Server OPs can use the command /spark profiler --timeout 180 to get a 3 minute snapshot of the server and anything that could be causing TPS issues. You can look at the URL returned by the mod to see an interactive online view of all server threads. Users can also use the command /spark profiler --only-ticks-over 100 --timeout 60, to identify intermittent lag spikes.
Note
For profiling client side FPS issues, use the sparkc command instead using same arguments above.
Observable¶
Observable has the same permission requirements, but users need to set a keybind in their Keybinds settings to open the UI, from there click the profile TPS button and wait for it to complete, then depending on the mc version, you will either get a url, or an in-game table listing what blocks/entities are costing the most TPS, it will also visually highlight blocks with a spectrum color coding from Green to Red, with things colored in red generally being the worst for performance.
Observable is an in-game profiler that can be used by anyone (1.20+, enabled by default in ATM9 and must create a keybind). In order to use the “Visit” button on the web page, you must be op.
Crash Utilities (Item Clear)¶
By default, Crash Utilities comes with most of our packs, though one feature Item Clear is disabled. It’s a very handy feature to have enabled with packs containing farms and automation to prevent massive entity leaks, which causes lag & crashes. This can keep your server entity count low for better performance.
To enable, locate and open world/serverconfigs/crashutilities-server.toml. Very top section, set enabled to true. The timer is the amount of time in minutes entities will be checked, followed by an Item Clear chat announcement when the entities goes over the maximum threshold.
When editing configs, please make sure server / client is not running
For clients, it’s safe to edit world/serverconfigs/ while not in the world and or restarting entire client.
Useful Commands¶
General Commands
Command may need to be executed more than once to clear all entities. Additionally, the Crash Utilities entities list command can be used to locate entities before they’re cleared.Spark
--only-ticks-over 20 argument will record only ticks that’s over 20 that’s considered problematic.
--thread * can help record all threads Spark may not pick up.