--- a/src/hotspot/share/gc/g1/g1RemSet.cpp	Thu Nov 23 15:51:06 2017 +0100
+++ b/src/hotspot/share/gc/g1/g1RemSet.cpp	Thu Nov 23 15:51:06 2017 +0100
@@ -298,7 +298,7 @@
 }
 
 uint G1RemSet::num_par_rem_sets() {
-  return MAX2(DirtyCardQueueSet::num_par_ids() + G1ConcurrentRefine::thread_num(), ParallelGCThreads);
+  return MAX2(DirtyCardQueueSet::num_par_ids() + G1ConcurrentRefine::max_num_threads(), ParallelGCThreads);
 }
 
 void G1RemSet::initialize(size_t capacity, uint max_regions) {