JMH and JDK 13

[Lev Serebryakov]

 I'm trying to run benchmarks of Panama code (or, to be more precise, my
code, which uses new Panama featrues) on JDK 13 on Windows. And my
results are wildely depends on output!

 First of all, JDK complains:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by org.openjdk.jmh.util.Utils
(file:/C:/home/lev/Projects/panama-benchmarks/vector/build/libs/vector-benc
hmark.jar) to field java.io.PrintStream.charOut
WARNING: Please consider reporting this to the maintainers of
org.openjdk.jmh.util.Utils
WARNING: Use --illegal-access=warn to enable warnings of further illegal
reflective access operations
WARNING: All illegal access operations will be denied in a future release

 But it is not main problem. Main problem is, that there is my benchmark
with simple "java -jar benchmark.jar:

# Warmup: 5 iterations, 10 s each
# Measurement: 10 iterations, 2 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: vector.VectorBenchmarks.VOVec_cs_div_cv
# Parameters: (callSize = 16, startOffset = 0)

# Run progress: 0,00% complete, ETA 00:14:00
# Fork: 1 of 2
# Warmup Iteration   1: 7448,058 ops/s
# Warmup Iteration   2: 7671,674 ops/s
# Warmup Iteration   3: 7632,154 ops/s
# Warmup Iteration   4: 7591,418 ops/s
# Warmup Iteration   5: 7645,616 ops/s
Iteration   1: 7629,146 ops/s
Iteration   2: 7644,162 ops/s
Iteration   3: 7640,662 ops/s
Iteration   4:^C

But I if I add "-XX:+PrintCompilation" and then filter-out all this
diagnostic output (which is not simple) I see:

# Warmup Iteration   1:     467
# Warmup Iteration   2:   11584
# Warmup Iteration   3:   21533
# Warmup Iteration   4:   31547
# Warmup Iteration   5:   41582
Iteration   1:   50571
Iteration   2:   54600
Iteration   4:   58630
Iteration   5:   59635
Iteration   6:   61649
Iteration   7:   65679
Iteration   8:   67694
Iteration   9:   67694
Iteration  10:   69710

 I'm not sure, is it JMH problem or JDK problem, but I can not good way
to check.

 BTW, adding `-o' option to benchmark run doesn't change result.







-- 
// Black Lion AKA Lev Serebryakov