etil2jz / etil-minecraft-flags

An extra optimization to Aikar flags, the JVM arguments that make your Minecraft server smooth.

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etil-minecraft-flags's Issues

Remove -XX:-UseBiasedLocking

UseBiasedLocking is disabled by default in JDK 15~
and it is deprecated.

Client Flags?

Hi,

first of all, thanks for your work on this, it's great to have an up to date source for these kind of JVM tweaks.

Would these flags also be helpful for a client or are they only geared towards servers and would hinder client performance? If so it would be great to have two sections like "Server Flags" and "Client Flags" to be able to optimize the clients as well, especially the heavily modded ones.

Module jdk.incubator.vector not found

/root/graalvm/graalvm-ee-java11-21.3.0/bin/java -server -Xms32G -Xmx32G -XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200 -XX:+UnlockExperimentalVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+DisableExplicitGC -XX:+AlwaysPreTouch -XX:G1NewSizePercent=40 -XX:G1MaxNewSizePercent=50 -XX:G1HeapRegionSize=16M -XX:G1ReservePercent=15 -XX:G1HeapWastePercent=5 -XX:G1MixedGCCountTarget=4 -XX:InitiatingHeapOccupancyPercent=20 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:SurvivorRatio=32 -XX:+PerfDisableSharedMem -XX:MaxTenuringThreshold=1 -Dusing.aikars.flags=https://mcflags.emc.gs -Daikars.new.flags=true -XX:-UseBiasedLocking -XX:+EnableJVMCIProduct -XX:+EnableJVMCI -XX:+UseJVMCICompiler -XX:+EagerJVMCI -XX:UseAVX=2 -XX:+UseStringDeduplication -XX:+UseFastUnorderedTimeStamps -XX:+UseAES -XX:+UseAESIntrinsics -XX:UseSSE=4 -XX:AllocatePrefetchStyle=1 -XX:+UseLoopPredicate -XX:+RangeCheckElimination -XX:+EliminateLocks -XX:+DoEscapeAnalysis -XX:+UseCodeCacheFlushing -XX:+UseFastJNIAccessors -XX:+OptimizeStringConcat -XX:+UseCompressedOops -XX:+UseThreadPriorities -XX:+OmitStackTraceInFastThrow -XX:+TrustFinalNonStaticFields -XX:ThreadPriorityPolicy=1 -XX:+UseInlineCaches -XX:+RewriteBytecodes -XX:+RewriteFrequentPairs -XX:+UseNUMA -XX:-DontCompileHugeMethods -XX:+UseCMoveUnconditionally -XX:+UseFPUForSpilling -XX:+UseNewLongLShift -XX:+UseVectorCmov -XX:+UseXMMForArrayCopy -XX:+UseXmmI2D -XX:+UseXmmI2F -XX:+UseXmmLoadAndClearUpper -XX:+UseXmmRegToRegMoveAll -Dfile.encoding=UTF-8 -Djdk.nio.maxCachedBufferSize=262144 -Dgraal.TuneInlinerExploration=1 -Dgraal.CompilerConfiguration=enterprise -Dgraal.UsePriorityInlining=true -Dgraal.Vectorization=true -Dgraal.OptDuplication=true -Dgraal.DetectInvertedLoopsAsCounted=true -Dgraal.LoopInversion=true -Dgraal.VectorizeHashes=true -Dgraal.EnterprisePartialUnroll=true -Dgraal.VectorizeSIMD=true -Dgraal.StripMineNonCountedLoops=true -Dgraal.SpeculativeGuardMovement=true -Dgraal.InfeasiblePathCorrelation=true --add-modules jdk.incubator.vector -jar forge-1.16.5-36.2.8.jar nogui

after

Java HotSpot(TM) 64-Bit Server VM warning: Max heap size too large for Compressed Oops
Java HotSpot(TM) 64-Bit Server VM warning: UseAVX=2 is not supported on this CPU, setting it to UseAVX=1
Error occurred during initialization of boot layer
java.lang.module.FindException: Module jdk.incubator.vector not found

what does this do --add-modules jdk.incubator.vector

GraalVM Regression

I noticed you switched to recommending Adoptium instead. If its because the current GraalVM release is buggy/erroring, I think I narrowed that down:

oracle/graal#4772
oracle/graal#4775

In a nutshell, you want to add the flags -Dgraal.VectorizeSIMD=false -Dgraal.UsePriorityInlining=false

But you mentioned a memory leak... could you elaborate on that some?

Crash

OpenJDK 64-Bit Server VM warning: Option UseBiasedLocking was deprecated in version 15.0 and will likely be removed in a future release.
OpenJDK 64-Bit Server VM warning: -XX:ThreadPriorityPolicy=1 may require system level permission, e.g., being the root user. If the necessary permission is not possessed, changes to priority will be silently ignored.
WARNING: Using incubator modules: jdk.incubator.vector
Error parsing Graal options: Could not find option LoopInversion
Error: A fatal exception has occurred. Program will exit.

I am using Fabric with GraalVM 17.

explain the flags and what they do?

java17 can't use this flags

"Cannot use JVMCI compiler: No JVMCI compiler found"
https://openjdk.java.net/jeps/410

a few questions

1. minecraft 1.16.5 (with mods) and older only support up to java 8, do you have any specific recommendations for this version ?
2. do you have flags recommendations for clients ?
3. i remember reading something about "large pages" on aikar's site, did you take that into account when saying to avoid using more than 20 gigs ?

Flags for Bungeecord

Hello, just wondering, are these flags also usefull for bungeecord? if not, what would be the bests ones for it? Thanks!

Error

Starting process: /usr/bin/java -Xms14G -Xmx14G -XX:+UseG1GC -XX:+ParallelRefProcEnabled -XX:MaxGCPauseMillis=200 -XX:+UnlockExperimentalVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+DisableExplicitGC -XX:+AlwaysPreTouch -XX:G1NewSizePercent=40 -XX:G1MaxNewSizePercent=50 -XX:G1HeapRegionSize=16M -XX:G1ReservePercent=15 -XX:G1HeapWastePercent=5 -XX:G1MixedGCCountTarget=4 -XX:InitiatingHeapOccupancyPercent=20 -XX:G1MixedGCLiveThresholdPercent=90 -XX:G1RSetUpdatingPauseTimePercent=5 -XX:SurvivorRatio=32 -XX:+PerfDisableSharedMem -XX:MaxTenuringThreshold=1 -Dusing.aikars.flags=https://mcflags.emc.gs -Daikars.new.flags=true -XX:-UseBiasedLocking -XX:+EnableJVMCIProduct -XX:+EnableJVMCI -XX:+UseJVMCICompiler -XX:+EagerJVMCI -XX:UseAVX=2 -XX:+UseStringDeduplication -XX:+UseFastUnorderedTimeStamps -XX:+UseAES -XX:+UseAESIntrinsics -XX:UseSSE=4 -XX:AllocatePrefetchStyle=1 -XX:+UseLoopPredicate -XX:+RangeCheckElimination -XX:+EliminateLocks -XX:+DoEscapeAnalysis -XX:+UseCodeCacheFlushing -XX:+UseFastJNIAccessors -XX:+OptimizeStringConcat -XX:+UseCompressedOops -XX:+UseThreadPriorities -XX:+OmitStackTraceInFastThrow -XX:+TrustFinalNonStaticFields -XX:ThreadPriorityPolicy=1 -XX:+UseInlineCaches -XX:+RewriteBytecodes -XX:+RewriteFrequentPairs -XX:+UseNUMA -XX:-DontCompileHugeMethods -XX:+UseCMoveUnconditionally -XX:+UseFPUForSpilling -XX:+UseNewLongLShift -XX:+UseVectorCmov -XX:+UseXMMForArrayCopy -XX:+UseXmmI2D -XX:+UseXmmI2F -XX:+UseXmmLoadAndClearUpper -XX:+UseXmmRegToRegMoveAll -Dfile.encoding=UTF-8 -Djdk.nio.maxCachedBufferSize=262144 -Dgraal.TuneInlinerExploration=1 -Dgraal.CompilerConfiguration=enterprise -Dgraal.UsePriorityInlining=true -Dgraal.Vectorization=true -Dgraal.OptDuplication=true -Dgraal.DetectInvertedLoopsAsCounted=true -Dgraal.LoopInversion=true -Dgraal.VectorizeHashes=true -Dgraal.EnterprisePartialUnroll=true -Dgraal.VectorizeSIMD=true -Dgraal.StripMineNonCountedLoops=true -Dgraal.SpeculativeGuardMovement=true -jar purpurclip.jarJava HotSpot(TM) 64-Bit Server VM warning: Option UseBiasedLocking was deprecated in version 15.0 and will likely be removed in a future release.
Java HotSpot(TM) 64-Bit Server VM warning: -XX:ThreadPriorityPolicy=1 may require system level permission, e.g., being the root user. If the necessary permission is not possessed, changes to priority will be silently ignored.
Java HotSpot(TM) 64-Bit Server VM warning:
The hardware does not support invariant tsc (INVTSC) register and/or cannot guarantee tsc synchronization between sockets at startup.
Values returned via rdtsc() are not guaranteed to be accurate, esp. when comparing values from cross sockets reads. Enabling UseFastUnorderedTimeStamps on non-invariant tsc hardware should be considered experimental.

Cannot use JVMCI compiler: No JVMCI compiler found

Superuser permission

Hi, I tried your flags with Graal EE with a non root account and I had this warning at startup
Java HotSpot(TM) 64-Bit Server VM warning: -XX:ThreadPriorityPolicy=1 may require system level permission, e.g., being the root user. If the necessary permission is not possessed, changes to priority will be silently ignored.

Can I ignore this or should I run the server with the root user?