RFR: Enable worker scaling for ref-proc

[Roman Kennke]

Recently I added the infra for worker-scaling for reference-processor,
but overlooked that I need to enable it too:

diff --git a/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
b/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
+++ b/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
@@ -2116,7 +2116,8 @@
                            true,                    // MT discovery
                            _max_workers,            // Degree of MT
discovery
                            false,                   // Reference
discovery is not atomic
-                           NULL);                   // No closure,
should be installed before use
+                           NULL,                    // No closure,
should be installed before use
+                           true);                   // Scale worker threads

   shenandoah_assert_rp_isalive_not_installed();
 }


Testing: tier3_gc_shenandoah running


Roman