8015244: G1: Verification after a full GC is incorrectly placed.
Summary: In a full GC, move the verification after the GC to after RSet rebuilding. Verify RSet entries during a full GC under control of a flag.
Reviewed-by: tschatzl, brutisso
--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Tue May 28 09:32:06 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp Tue Jun 04 10:04:06 2013 -0700
@@ -1417,8 +1417,6 @@
MemoryService::track_memory_usage();
- verify_after_gc();
-
assert(!ref_processor_stw()->discovery_enabled(), "Postcondition");
ref_processor_stw()->verify_no_references_recorded();
@@ -1521,6 +1519,8 @@
_hrs.verify_optional();
verify_region_sets_optional();
+ verify_after_gc();
+
// Start a new incremental collection set for the next pause
assert(g1_policy()->collection_set() == NULL, "must be");
g1_policy()->start_incremental_cset_building();
--- a/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Tue May 28 09:32:06 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1RemSet.cpp Tue Jun 04 10:04:06 2013 -0700
@@ -736,7 +736,7 @@
void G1RemSet::prepare_for_verify() {
if (G1HRRSFlushLogBuffersOnVerify &&
(VerifyBeforeGC || VerifyAfterGC)
- && !_g1->full_collection()) {
+ && (!_g1->full_collection() || G1VerifyRSetsDuringFullGC)) {
cleanupHRRS();
_g1->set_refine_cte_cl_concurrency(false);
if (SafepointSynchronize::is_at_safepoint()) {
--- a/hotspot/src/share/vm/gc_implementation/g1/g1_globals.hpp Tue May 28 09:32:06 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1_globals.hpp Tue Jun 04 10:04:06 2013 -0700
@@ -329,7 +329,11 @@
\
develop(bool, G1EvacuationFailureALotDuringMixedGC, true, \
"Force use of evacuation failure handling during mixed " \
- "evacuation pauses")
+ "evacuation pauses") \
+ \
+ diagnostic(bool, G1VerifyRSetsDuringFullGC, false, \
+ "If true, perform verification of each heap region's " \
+ "remembered set when verifying the heap during a full GC.")
G1_FLAGS(DECLARE_DEVELOPER_FLAG, DECLARE_PD_DEVELOPER_FLAG, DECLARE_PRODUCT_FLAG, DECLARE_PD_PRODUCT_FLAG, DECLARE_DIAGNOSTIC_FLAG, DECLARE_EXPERIMENTAL_FLAG, DECLARE_NOTPRODUCT_FLAG, DECLARE_MANAGEABLE_FLAG, DECLARE_PRODUCT_RW_FLAG)
--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Tue May 28 09:32:06 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegion.cpp Tue Jun 04 10:04:06 2013 -0700
@@ -139,7 +139,7 @@
_n_failures++;
}
- if (!_g1h->full_collection()) {
+ if (!_g1h->full_collection() || G1VerifyRSetsDuringFullGC) {
HeapRegion* from = _g1h->heap_region_containing((HeapWord*)p);
HeapRegion* to = _g1h->heap_region_containing(obj);
if (from != NULL && to != NULL &&