--- old/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	2018-09-05 21:55:19.941680091 -0700
+++ new/src/hotspot/share/gc/g1/g1CollectedHeap.cpp	2018-09-05 21:55:19.522640189 -0700
@@ -2900,8 +2900,9 @@
     active_workers = workers()->update_active_workers(active_workers);
     log_info(gc,task)("Using %u workers of %u for evacuation", active_workers, workers()->total_workers());
 
+    bool full_gc = (gc_cause() == GCCause::_java_lang_system_gc);
     G1MonitoringScope ms(g1mm(),
-                         false /* full_gc */,
+                         full_gc /* full_gc */,
                          collector_state()->yc_type() == Mixed /* all_memory_pools_affected */);
 
     G1HeapTransition heap_transition(this);
--- /dev/null	2018-04-29 16:09:36.328000000 -0700
+++ new/test/hotspot/jtreg/gc/g1/TestTenuredGenPoolCollectionUsage.java	2018-09-05 21:55:20.407724468 -0700
@@ -0,0 +1,68 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test TestTenuredGenPoolCollectionUsage
+ * @bug 8175375
+ * @requires vm.gc.G1 
+ * @summary Verify that MemoryPoolMXBean.getCollectionUsage() works fine with
+ * -XX:+UseG1GC and -XX:+ExplicitGCInvokesConcurrent
+ * @library /test/lib /
+ * @modules java.base/jdk.internal.misc
+ * @modules java.management/sun.management
+ * @run main/othervm -XX:+ExplicitGCInvokesConcurrent -XX:+UseG1GC
+ * TestTenuredGenPoolCollectionUsage
+ */
+
+import java.util.ArrayList;
+import java.util.List;
+import java.lang.management.ManagementFactory;
+import java.lang.management.MemoryPoolMXBean;
+import java.lang.management.MemoryType;
+import jdk.test.lib.Asserts;
+
+public class TestTenuredGenPoolCollectionUsage {
+
+    public static void main(String[] args) {
+        new TestTenuredGenPoolCollectionUsage().test();
+    }
+
+    private final void test() {
+        MemoryPoolMXBean tenuredGenPool = null;
+        List<byte[]> data = new ArrayList<>();
+        for (MemoryPoolMXBean pool : ManagementFactory.getMemoryPoolMXBeans()) {
+            if (pool.getType() == MemoryType.HEAP && pool.isUsageThresholdSupported()) {
+                tenuredGenPool = pool;
+            }
+        }
+        data.add(new byte[1024 * 1024 * 50]);
+        try {
+            Thread.sleep(100);
+        } catch(InterruptedException ie) {
+            ie.printStackTrace();
+        }
+        System.gc();
+        System.out.println("Collection usage = " + tenuredGenPool.getCollectionUsage().getUsed() + ", usage = " + tenuredGenPool.getUsage().getUsed());
+        Asserts.assertTrue(tenuredGenPool.getCollectionUsage().getUsed() > 0);
+    }
+}