mojira.dev
MC-103656

Excessive use of System.gc()

General issue: Some "lags" when playing on a local minecraft server. Example, mobs and players are moving "step-by-step".
Monitoring CPU, RAM and Disk usage, it appears than the computer does almost "nothing". RAM usage is under 10% in the JVM (when i'm connected alone, locally).

Command line with options used for the tests : java -server -Xmx2G -Xms2G -jar minecraft_server.1.10.jar
I also tried with 4GB, 8GB, and with several GC options.

After adding garbage collector logging flags on the command line, i was quickly able to see a lot of (useless) calls to "System.gc()". In my opinion, and knowing the java language, this is not a good thing. I guess the repeated call to this procedure is not intentional.

To be sure, I added the "-XX:+DisableExplicitGC" flag to the command line, and this solved the issue.

I think that adding "-XX:+DisableExplicitGC" to the arguments should only be a workaround, and that a "real" fix (removing the problematic System.gc() call) should be released.

Thank you 🙂

Related issues

Comments

md_5

Running with nogui should also remove these GC calls.

migrated

Is this still an issue in the latest snapshot 16w44a? If so please update the affected versions.

This is an automated comment on any open or reopened issue with out-of-date affected versions.

wobst.michael

Is this still an issue in the most recent versions (currently that is 1.12.2, or the latest 1.13 development snapshot 18w07c) of Minecraft?

md_5

Yes to both

Uriel Salischiker

Is this still a issue in the latest version of the game(currently 1.13.1)?

If so, please add it to the affected versions, thanks!

md_5

Resolved in 1.13

migrated

(Unassigned)

Unconfirmed

Minecraft 1.10, Minecraft 1.12.2, Minecraft 18w07c

Minecraft 1.13.1

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