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For adaptive compilation profile
Panel

-X:aos:enable_advice_generation=true


-X:aos:cafo=my_compiler_advice_file.ca

For edge count profile
Panel

-X:base:profile_edge_counters=true


-X:base:profile_edge_counter_file=my_edge_counter_file.ec

For dynamic call graph profile
Panel

-X:aos:dcfo=my_dynamic_call_graph_file.dc


-X:aos:final_report_level=2 

Executing with advice.

The basic model is simple.  At a nominated time in the execution of a program, all methods specified in the .ca advice file will be (re)compiled with the compiler and optimization level nominated in the advice file.  Broadly, there are two ways of initiating bulk compilation: a) by calling the method org.jikesrvm.adaptive.recompilation.BulkCompile.compileAllMethods() during execution, and b) by using the -X:aos:enable_precompile=true flag at the command line to trigger bulk compilation at boot time.  A standard methodology is to use a benchmark harness call back mechanism to call compileAllMethods() at the end of the first iteration of the benchmark.   At the time of writing this gave performance roughly 2% faster than the 10th iteration of regular adaptive compilation.  Because precompilation occurs early, the compiler has less information about the classes, and in consequence the performance of precompilation is about 9% slower than the 10th iteration of adaptive compilation.

For 'warmup' replay (where org.jikesrvm.adaptive.recompilation.BulkCompile.compileAllMethods() is called at the end of the first iteration):

Panel

-X:aos:initial_compiler=base -X:aos:enable_bulk_compile=true -X:aos:enable_recompilation=false -X:aos:cafi=benchmark.ca -X:vm:edgeCounterFile=benchmark.ec -X:aos:dcfi=benchmark.dc

For precompile replay (where bulk compilation occurs at boot time):

Panel

-X:aos:initial_compiler=base -X:aos:enable_precompile=true -X:aos:enable_recompilation=false -X:aos:cafi=benchmark.ca -X:vm:edgeCounterFile=benchmark.ec -X:aos:dcfi=benchmark.dc

 

Measuring GC performance

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