RFR 8221623 : Add StackWalker micro benchmarks to jdk repo

[Daniel Fuchs]

Hi Brent,

The StackWalker benchmark look good to me.
However I have some doubts about the the logging benchmark.

Is the benchmark run in a single thread? If not then
there doesn't seem any guarantee that each call to publish()
will be immediately followed by a call to reset(), but instead,
if you have two threads, you could see things like:

T1: publish();
T2: publish();   => T1 record would be lost here
T1: reset();
T2: reset();     => reset() would return null here

best regards,

-- daniel

On 13/09/2019 23:07, Brent Christian wrote:
> Hi,
> 
> Please review these StackWalker and Throwable benchmarks for addition 
> into the JDK microbenchmarks.
> 
> Bug:
> https://bugs.openjdk.java.net/browse/JDK-8221623
> Webrev:
> http://cr.openjdk.java.net/~bchristi/8221623/webrev07/
> 
> The StackWalker benchmarks use StackWalker's forEach(), walk(), and 
> Options to measure retrieval of various types of information from the 
> call stack.
> 
> The Throwable benchmarks do corresponding exercises; there are also a 
> couple of Logging benchmarks.
> 
> A JMH @Param is used to test a variety of call stack depths.
> 
> 
> In the future, we might consider a benchmark for 
> Reflection.getCallerClass().  (It is more involved today to benchmark 
> that method than at the time these benchmarks were originally written, 
> so that one's commented out.) See JDK-8230976.
> 
> Thanks,
> -Brent
> 
> 1. https://bugs.openjdk.java.net/browse/JDK-8230976