% java -jar jcstress-samples/target/jcstress.jar -t API_01_Simple
Java Concurrency Stress Tests
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Rev: 9ed7ac43bacc6d99, built by pavelrappo with 23.0.2 at 2025-06-06T17:32:23Z

Burning up to figure out the exact CPU count....... done!

Probing the target OS:
 (all failures are non-fatal, but may affect testing accuracy)

----- [N/A] Trying to set global affinity with taskset
Cannot run program "taskset": error=2, No such file or directory
----- [N/A] Trying to set per-thread affinity with syscalls
Not implemented

Initializing and probing the target VM:
 (all failures are non-fatal, but may affect testing accuracy)

----- [OK] Unlocking diagnostic VM options
----- [OK] Disabling performance data collection
----- [OK] Checking for C1 availability
----- [OK] Checking for C2 availability
----- [N/A] Checking for biased locking support
----- [OK] Trimming down the VM heap size to 256M
----- [OK] Enabling Java heap pre-touch
----- [OK] Trimming down the number of parallel GC threads
----- [OK] Trimming down the number of concurrent GC threads
----- [OK] Trimming down the number of G1 concurrent refinement GC threads
----- [OK] Trimming down the number of compiler threads
----- [OK] Testing @Contended works on all results and infra objects
----- [OK] Unlocking debug information for non-safepoints
----- [OK] Disabling verification on exit
----- [OK] Disabling Thread SMR statistics
----- [N/A] Disabling debug JVM zapping: unused heap
----- [N/A] Disabling debug JVM zapping: TLABs
----- [N/A] Disabling debug JVM zapping: filler objects
----- [N/A] Disabling debug JVM zapping: resource area
----- [N/A] Disabling debug JVM zapping: VM handle area
----- [N/A] Disabling debug JVM zapping: stack segments
----- [N/A] Disabling debug JVM verification: compilation dependencies
----- [OK] Unlocking C2 local code motion randomizer
----- [OK] Unlocking C2 global code motion randomizer
----- [OK] Unlocking C2 iterative global value numbering randomizer
----- [OK] Unlocking C2 conditional constant propagation randomizer
----- [OK] Unlocking C2 incremental inlining randomizer
----- [OK] Unlocking C2 macro expansion randomizer
----- [OK] Checking if C2 randomizers accept stress seed
----- [OK] Testing allocation profiling
----- [OK] Testing Thread.onSpinWait
----- [OK] Testing PrintAssembly
----- [OK] Testing compiler directives

Probing what VM configurations are available:
 (failures are non-fatal, but may miss some interesting cases)
 (split compilation is requested and compiler directives are available)

----- [OK] []
----- [OK] [-XX:+StressLCM, -XX:+StressGCM, -XX:+StressIGVN, -XX:+StressCCP, -XX:+StressIncrementalInlining, -XX:+StressMacroExpansion]

Exception in thread "main" java.lang.NullPointerException
at java.base/java.io.Reader.<init>(Reader.java:168)
at java.base/java.io.InputStreamReader.<init>(InputStreamReader.java:89)
at org.openjdk.jcstress.infra.runners.TestList.getTests(TestList.java:51)
at org.openjdk.jcstress.infra.runners.TestList.tests(TestList.java:104)
at org.openjdk.jcstress.JCStress.getTests(JCStress.java:222)
at org.openjdk.jcstress.JCStress.getConfigs(JCStress.java:99)
at org.openjdk.jcstress.JCStress.run(JCStress.java:59)
at org.openjdk.jcstress.Main.main(Main.java:57)



^ The above NPE is thrown because there's no /META-INF/TestList, which should be generated by org.openjdk.jcstress.infra.processors.JCStressTestProcessor.

See also: https://mail.openjdk.org/pipermail/jdk-dev/2024-May/009028.html