asmhatre/zgc-jdk25-benchmarks
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Add flags: production JVM flag cheat sheet for Spring Boot on JDK 25/27

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MaxRAMPercentage vs a hardcoded -Xmx, -XX:-UseContainerSupport, the
ActiveProcessorCount lie, and which diagnostic flags are worth leaving
on in prod, verified in real Docker containers on JDK 25 and JDK 27.

Co-Authored-By: Claude Sonnet 5 <[email protected]>
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asmhatre
2026-10-01 04:34:04 +00:00
co-authored by Claude Sonnet 5
parent e83c9949d8
commit 2f88734f5d
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@@ -72,6 +72,7 @@ the part most "ZGC is faster" posts leave out.
| [`analysis/GcLogParser.java`](analysis/src/com/ankurm/zgc/analysis/GcLogParser.java) | Unified-log parser that keeps pauses and concurrent phases apart | none |
| [`jmh/`](jmh/src/main/java/com/ankurm/zgc/jmh) | Throughput and barrier microbenchmarks | JMH 1.37 |
| [`jdk27-memory/`](jdk27-memory) | Spring Boot 4.1 service measured on JDK 25, 26 and 27: compact object headers (JEP 534) and G1 everywhere (JEP 523), heap footprint, container sizing with real cgroup limits. Its README and `output/` replace a `docs/` folder; the write-up is [the post](https://ankurm.com/jdk-27-compact-object-headers-g1-default-memory-spring-boot/) | Spring Boot 4.1.1, three JDKs |
| [`flags/`](flags) | The flag-by-flag production cheat sheet: `MaxRAMPercentage` vs a hardcoded `-Xmx` (one fails safely, one gets the container SIGKILLed), `-XX:-UseContainerSupport`, the `ActiveProcessorCount` lie, and which diagnostic flags (`HeapDumpOnOutOfMemoryError`, `NativeMemoryTracking`) are worth leaving on in prod — on real Docker containers, JDK 25 and JDK 27. Its README and `docs/output/` replace a `docs/` folder; the write-up is [the post](https://ankurm.com/jvm-flags-for-spring-boot-in-containers-jdk-25-27/) | Spring Boot 4.1.1, Docker, two JDKs |
### JMH benchmarks