anchor.diff:  (derived from a single random master seed).
   
   --------------------------------------------------
  -./gradlew test -Dtests.iters=N -Dtests.class=*.ClassName
  +./gradlew :server:test -Dtests.iters=N --tests org.elasticsearch.package.ClassName
   --------------------------------------------------
   
   === Repeats _all_ tests of ClassName N times.
  
positive.code: ending in a glob is necessary to ensure iterations are run).
  
  -------------------------------------------------------------------------
  ./gradlew test -Dtests.iters=N -Dtests.class=*.ClassName -Dtests.method=mytest*
  -------------------------------------------------------------------------
  
  Repeats N times but skips any tests after the first failure or M initial failures.
  
  -------------------------------------------------------------
  ./gradlew test -Dtests.iters=N -Dtests.failfast=true -Dtestcase=...
  ./gradlew test -Dtests.iters=N -Dtests.maxfailures=M -Dtestcase=...
  -------------------------------------------------------------
  
  === Test groups.
  
negative.code: ----------------------------
  
  Its difficult to pick the "right" number here. Hypercores don't count for CPU
  intensive tests and you should leave some slack for JVM-internal threads like
  the garbage collector. And you have to have enough RAM to handle each JVM.
  
  === Test compatibility.
  