Hi all,

      I noticed that the performance of master is better than GROOVY_2_5_X.

      About 17% time saved when running tests in the TeamCity CI instance:
master costs 18m:55s(TeamCity CI, Parrot disabled)
http://ci.groovy-lang.org/viewLog.html?buildId=38801&tab=buildResultsDiv&buildTypeId=Groovy_Jdk8Build_2
GROOVY_2_5_X costs 22m:51s(TeamCity CI, without Parrot)
http://ci.groovy-lang.org/viewLog.html?buildId=38787&tab=buildResultsDiv&buildTypeId=Groovy_Jdk8Build_2

      And about 37% time saved when running tests in the Travis CI instance:
master costs 20 min 25 sec(Travis CI, Parrot enabled)
https://travis-ci.org/apache/groovy/builds/223991099
GROOVY_2_5_X costs 32 min 52 sec(Travis CI, without Parrot)
https://travis-ci.org/apache/groovy/builds/223816724

      Can we infer that the new parser Parrot does not impact the performance or even improve the performance somehow?

Cheers,
Daniel.Sun