When oopstorage+ref trace logging is enabled the bulk (2-arg) form of OopStorage::release will log each released entry at 2-3 times instead of the desired once. This can be fixed by removing one of the log statements:

diff --git a/src/hotspot/share/gc/shared/oopStorage.cpp b/src/hotspot/share/gc/shared/oopStorage.cpp
index 416afce7034..d701c3e8cba 100644
--- a/src/hotspot/share/gc/shared/oopStorage.cpp
+++ b/src/hotspot/share/gc/shared/oopStorage.cpp
@@ -707,7 +707,6 @@ void OopStorage::release(const oop* const* ptrs, size_t size) {
     check_release_entry(ptrs[i]);
     Block* block = find_block_or_null(ptrs[i]);
     assert(block != NULL, "%s: invalid release " PTR_FORMAT, name(), p2i(ptrs[i]));
- log_trace(oopstorage, ref)("%s: released " PTR_FORMAT, name(), p2i(ptrs[i]));
     size_t count = 0;
     uintx releasing = 0;
     for ( ; i < size; ++i) {

(Thanks to Doug Simon for noticing this.)