src/share/vm/runtime/vm_version.cpp

*** 273,283 ****
  unsigned int Abstract_VM_Version::nof_parallel_worker_threads(
                                                        unsigned int num,
                                                        unsigned int den,
                                                        unsigned int switch_pt) {
    if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
!     assert(ParallelGCThreads == 0, "Default ParallelGCThreads is not 0");
      // For very large machines, there are diminishing returns
      // for large numbers of worker threads.  Instead of
      // hogging the whole system, use a fraction of the workers for every
      // processor after the first 8.  For example, on a 72 cpu machine
      // and a chosen fraction of 5/8
--- 273,284 ----
  unsigned int Abstract_VM_Version::nof_parallel_worker_threads(
                                                        unsigned int num,
                                                        unsigned int den,
                                                        unsigned int switch_pt) {
    if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
!     assert(_parallel_worker_threads_initialized ||
!            ParallelGCThreads == 0, "Default ParallelGCThreads is not 0");
      // For very large machines, there are diminishing returns
      // for large numbers of worker threads.  Instead of
      // hogging the whole system, use a fraction of the workers for every
      // processor after the first 8.  For example, on a 72 cpu machine
      // and a chosen fraction of 5/8
*** 307,311 ****
--- 308,324 ----
      }
      _parallel_worker_threads_initialized = true;
    }
    return _parallel_worker_threads;
  }
+ 
+ void  Abstract_VM_Version::FinalParallelGCThreads_test() {
+   // This consistency check should only be made if the user has not set
+   // a value on the command line and a ergonomically determined value 
+   // is used (i.e., _parallel_worker_threads_initialized is true).
+   if (FLAG_IS_DEFAULT(ParallelGCThreads) && _parallel_worker_threads_initialized) {
+     assert(ParallelGCThreads == VM_Version::calc_parallel_worker_threads(),
+       "ParallelGCThreads %u is different than that calculated after full VM initialization %u.",
+               ParallelGCThreads, VM_Version::calc_parallel_worker_threads());
+   }
+ }
+