--- old/src/hotspot/share/gc/shenandoah/shenandoahConcurrentMark.cpp	2019-06-14 16:50:52.922647071 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahConcurrentMark.cpp	2019-06-14 16:50:52.577646548 -0400
@@ -156,7 +156,7 @@
   void work(uint worker_id) {
     ShenandoahHeap* heap = ShenandoahHeap::heap();
     ShenandoahConcurrentWorkerSession worker_session(worker_id);
-    ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+    ShenandoahSuspendibleThreadSetJoiner stsj;
     ShenandoahObjToScanQueue* q = _cm->get_queue(worker_id);
     ReferenceProcessor* rp;
     if (heap->process_references()) {
@@ -982,7 +982,7 @@
     if (work == 0) {
       // No work encountered in current stride, try to terminate.
       // Need to leave the STS here otherwise it might block safepoints.
-      ShenandoahSuspendibleThreadSetLeaver stsl(CANCELLABLE && ShenandoahSuspendibleWorkers);
+      ShenandoahSuspendibleThreadSetLeaver stsl(CANCELLABLE);
       ShenandoahTerminationTimingsTracker term_tracker(worker_id);
       ShenandoahTerminatorTerminator tt(heap);
       if (terminator->offer_termination(&tt)) return;
--- old/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp	2019-06-14 16:50:53.749648322 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp	2019-06-14 16:50:53.401647796 -0400
@@ -949,7 +949,7 @@
   void work(uint worker_id) {
     if (_concurrent) {
       ShenandoahConcurrentWorkerSession worker_session(worker_id);
-      ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+      ShenandoahSuspendibleThreadSetJoiner stsj;
       ShenandoahEvacOOMScope oom_evac_scope;
       do_work();
     } else {
@@ -1872,7 +1872,6 @@
     jbyte prev = _cancelled_gc.cmpxchg(CANCELLED, CANCELLABLE);
     if (prev == CANCELLABLE) return true;
     else if (prev == CANCELLED) return false;
-    assert(ShenandoahSuspendibleWorkers, "should not get here when not using suspendible workers");
     assert(prev == NOT_CANCELLED, "must be NOT_CANCELLED");
     {
       // We need to provide a safepoint here, otherwise we might
@@ -2086,7 +2085,7 @@
   void work(uint worker_id) {
     if (_concurrent) {
       ShenandoahConcurrentWorkerSession worker_session(worker_id);
-      ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+      ShenandoahSuspendibleThreadSetJoiner stsj;
       do_work();
     } else {
       ShenandoahParallelWorkerSession worker_session(worker_id);
@@ -2286,15 +2285,11 @@
 }
 
 void ShenandoahHeap::safepoint_synchronize_begin() {
-  if (ShenandoahSuspendibleWorkers || UseStringDeduplication) {
-    SuspendibleThreadSet::synchronize();
-  }
+  SuspendibleThreadSet::synchronize();
 }
 
 void ShenandoahHeap::safepoint_synchronize_end() {
-  if (ShenandoahSuspendibleWorkers || UseStringDeduplication) {
-    SuspendibleThreadSet::desynchronize();
-  }
+  SuspendibleThreadSet::desynchronize();
 }
 
 void ShenandoahHeap::vmop_entry_init_mark() {
--- old/src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp	2019-06-14 16:50:54.582649584 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahHeap.inline.hpp	2019-06-14 16:50:54.241649068 -0400
@@ -187,7 +187,7 @@
 }
 
 inline bool ShenandoahHeap::check_cancelled_gc_and_yield(bool sts_active) {
-  if (! (sts_active && ShenandoahSuspendibleWorkers)) {
+  if (!sts_active) {
     return cancelled_gc();
   }
 
--- old/src/hotspot/share/gc/shenandoah/shenandoahTraversalGC.cpp	2019-06-14 16:50:55.367650773 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoahTraversalGC.cpp	2019-06-14 16:50:55.034650269 -0400
@@ -214,7 +214,7 @@
 
   void work(uint worker_id) {
     ShenandoahConcurrentWorkerSession worker_session(worker_id);
-    ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+    ShenandoahSuspendibleThreadSetJoiner stsj;
     ShenandoahEvacOOMScope oom_evac_scope;
     ShenandoahTraversalGC* traversal_gc = _heap->traversal_gc();
 
@@ -534,7 +534,7 @@
     if (work == 0) {
       // No more work, try to terminate
       ShenandoahEvacOOMScopeLeaver oom_scope_leaver;
-      ShenandoahSuspendibleThreadSetLeaver stsl(sts_yield && ShenandoahSuspendibleWorkers);
+      ShenandoahSuspendibleThreadSetLeaver stsl(sts_yield);
       ShenandoahTerminationTimingsTracker term_tracker(worker_id);
       ShenandoahTerminatorTerminator tt(_heap);
 
@@ -847,7 +847,7 @@
   void work(uint worker_id) {
     assert(worker_id == 0, "The code below is single-threaded, only one worker is expected");
     ShenandoahParallelWorkerSession worker_session(worker_id);
-    ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+    ShenandoahSuspendibleThreadSetJoiner stsj;
     ShenandoahEvacOOMScope oom_evac_scope;
 
     ShenandoahHeap* sh = ShenandoahHeap::heap();
--- old/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp	2019-06-14 16:50:56.177652000 -0400
+++ new/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp	2019-06-14 16:50:55.835651482 -0400
@@ -343,9 +343,6 @@
           "definitely alive references to avoid dealing with them during "  \
           "pause.")                                                         \
                                                                             \
-  experimental(bool, ShenandoahSuspendibleWorkers, false,                   \
-          "Suspend concurrent GC worker threads at safepoints")             \
-                                                                            \
   diagnostic(bool, ShenandoahSATBBarrier, true,                             \
           "Turn on/off SATB barriers in Shenandoah")                        \
                                                                             \
--- old/test/hotspot/jtreg/gc/shenandoah/TestAllocObjects.java	2019-06-14 16:50:56.954653177 -0400
+++ new/test/hotspot/jtreg/gc/shenandoah/TestAllocObjects.java	2019-06-14 16:50:56.621652673 -0400
@@ -45,12 +45,6 @@
  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=static       TestAllocObjects
  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=compact      TestAllocObjects
  * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=traversal    TestAllocObjects
- *
- * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=adaptive   -XX:+ShenandoahSuspendibleWorkers TestAllocObjects
- * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=static     -XX:+ShenandoahSuspendibleWorkers TestAllocObjects
- * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=compact    -XX:+ShenandoahSuspendibleWorkers TestAllocObjects
- * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=traversal  -XX:+ShenandoahSuspendibleWorkers TestAllocObjects
- * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx1g -Xms1g -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahSuspendibleWorkers TestAllocObjects
  */
 
 import java.util.Random;