RFR: 8261447: MethodInvocationCounters frequently run into overflow [v8]

[Lutz Schmidt]

> Dear community,
> may I please request reviews for this fix, improving the usefulness of method invocation counters.
> - aggregation counters are retyped as uint64_t, shifting the overflow probability way out (> 500 years in case of a 1 GHz counter update frequency).
> - counters for individual methods are interpreted as (unsigned int), in contrast to their declaration as int. This gives us a factor of two before the counters overflow.
> - as a special case, "compiled_invocation_counter" is retyped as long, because it has a higher update frequency than other counters.
> - before/after sample output is attached to the bug description. 
> 
> Thank you!
> Lutz

Lutz Schmidt has updated the pull request incrementally with one additional commit since the last revision:

  comment changes requested by TheRealMDoerr

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2511/files
  - new: https://git.openjdk.java.net/jdk/pull/2511/files/0f220ee3..e8af119b

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2511&range=07
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2511&range=06-07

  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2511.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2511/head:pull/2511

PR: https://git.openjdk.java.net/jdk/pull/2511