diff -r 714474295e0a -r b537e6386306 src/hotspot/share/memory/metaspace/leftOverBins.inline.hpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/memory/metaspace/leftOverBins.inline.hpp	Fri Nov 01 10:28:15 2019 +0100
@@ -0,0 +1,243 @@
+/*
+ * Copyright (c) 2019, SAP SE. All rights reserved.
+ * Copyright (c) 2019, 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.
+ *
+ */
+
+#ifndef SHARE_MEMORY_METASPACE_LEFTOVERBINS_INLINE_HPP
+#define SHARE_MEMORY_METASPACE_LEFTOVERBINS_INLINE_HPP
+
+#include "memory/allocation.hpp"
+#include "memory/metaspace/leftOverBins.hpp"
+#include "utilities/debug.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/ostream.hpp"
+
+namespace metaspace {
+
+
+// Starting at (including) pos, find the position of the next 1 bit.
+// Return -1 if not found.
+int BinMap::find_next_set_bit(int pos) const {
+  if (get_bit(pos)) {
+    return pos;
+  }
+  mask_type m2 = _mask;
+  int pos2 = pos + 1;
+  m2 >>= pos2;
+  if (m2 > 0) {
+    while ((m2 & (mask_type)1) == 0) {
+      m2 >>= 1;
+      pos2 ++;
+    }
+    return pos2;
+  }
+  return -1;
+}
+
+///////////////////////////////////////
+
+template <size_t min_word_size, size_t spread, int num_bins>
+void Bins<min_word_size, spread, num_bins>::put(MetaWord* p, size_t word_size) {
+  assert(word_size >= minimal_word_size() && word_size < maximal_word_size(), "Invalid word size");
+  block_t* b = (block_t*)p;
+  int bno = bin_for_size(word_size);
+  assert(bno >= 0 && bno < num_bins, "Sanity");
+  assert(b != _bins[bno], "double add?");
+  b->next = _bins[bno];
+  b->size = word_size;
+  _bins[bno] = b;
+  _mask.set_bit(bno);
+}
+
+template <size_t min_word_size, size_t spread, int num_bins>
+block_t* Bins<min_word_size, spread, num_bins>::get(size_t word_size) {
+  // Adjust size for spread (we need the bin number which guarantees word_size).
+  word_size += (spread - 1);
+  if (word_size >= maximal_word_size()) {
+    return NULL;
+  }
+  int bno = bin_for_size(word_size);
+  bno = _mask.find_next_set_bit(bno);
+  if (bno != -1) {
+    assert(bno >= 0 && bno < num_bins, "Sanity");
+    assert(_bins[bno] != NULL, "Sanity");
+    block_t* b = _bins[bno];
+    _bins[bno] = b->next;
+    if (_bins[bno] == NULL) {
+      _mask.clr_bit(bno);
+    }
+    return b;
+  }
+  return NULL;
+}
+
+#ifdef ASSERT
+template <size_t min_word_size, size_t spread, int num_bins>
+void Bins<min_word_size, spread, num_bins>::verify() const {
+  for (int i = 0; i < num_bins; i ++) {
+    assert(_mask.get_bit(i) == (_bins[i] != NULL), "Sanity");
+    const size_t min_size = minimal_word_size_in_bin(i);
+    const size_t max_size = maximal_word_size_in_bin(i);
+    for(block_t* b = _bins[i]; b != NULL; b = b->next) {
+      assert(b->size >= min_size && b->size < max_size, "Sanity");
+    }
+  }
+}
+#endif // ASSERT
+
+
+template <size_t min_word_size, size_t spread, int num_bins>
+void Bins<min_word_size, spread, num_bins>::statistics(block_stats_t* stats) const {
+  for (int i = 0; i < num_bins; i ++) {
+    for(block_t* b = _bins[i]; b != NULL; b = b->next) {
+      stats->num_blocks ++;
+      stats->word_size += b->size;
+    }
+  }
+}
+
+template <size_t min_word_size, size_t spread, int num_bins>
+void Bins<min_word_size, spread, num_bins>::print(outputStream* st) const {
+  bool first = true;
+  for (int i = 0; i < num_bins; i ++) {
+    int n = 0;
+    for(block_t* b = _bins[i]; b != NULL; b = b->next) {
+      n ++;
+    }
+    if (n > 0) {
+      if (!first) {
+        st->print(", ");
+      } else {
+        first = false;
+      }
+      st->print(SIZE_FORMAT "=%d", minimal_word_size_in_bin(i), n);
+    }
+  }
+}
+
+
+
+///////////////////////////////////////
+
+// Take the topmost block from the large block reserve list
+// and make it current.
+inline void LeftOverManager::prime_current() {
+  if (_large_block_reserve != NULL) {
+    _current = (MetaWord*) _large_block_reserve;
+    _current_size = _large_block_reserve->size;
+    _large_block_reserve = _large_block_reserve->next;
+  } else {
+    _current = NULL;
+    _current_size = 0;
+  }
+}
+
+// Allocate from current block. Returns NULL if current block
+// is too small.
+inline MetaWord* LeftOverManager::alloc_from_current(size_t word_size) {
+  if (_current_size >= word_size) {
+    assert(_current != NULL, "Must be");
+    MetaWord* p = _current;
+    size_t remaining = _current_size - word_size;
+    if (remaining >= _very_small_bins.minimal_word_size()) {
+      _current = p + word_size;
+      _current_size = remaining;
+    } else {
+      // completely used up old large block. Proceed to next.
+      prime_current();
+    }
+    return p;
+  }
+  return NULL;
+}
+
+inline void LeftOverManager::add_block(MetaWord* p, size_t word_size) {
+  if (word_size >= minimal_word_size()) {
+    if (word_size < _very_small_bins.maximal_word_size()) {
+      _very_small_bins.put(p, word_size);
+    } else {
+      if (_current == NULL) {
+        assert(_large_block_reserve == NULL, "Should be primed.");
+        _current = p;
+        _current_size = word_size;
+      } else {
+        assert(sizeof(block_t) <= word_size * BytesPerWord, "must be");
+        block_t* b = (block_t*)p;
+        b->size = word_size;
+        b->next = _large_block_reserve;
+        _large_block_reserve = b;
+      }
+    }
+    _total_word_size.increment_by(word_size);
+  }
+
+  DEBUG_ONLY(verify();)
+
+}
+
+inline MetaWord* LeftOverManager::get_block(size_t requested_word_size) {
+
+  requested_word_size = MAX2(requested_word_size, minimal_word_size());
+
+  // First attempt to take from current large block because that is cheap (pointer bump)
+  // and efficient (no spread)
+  MetaWord* p = alloc_from_current(requested_word_size);
+  if (p == NULL && _current_size > 0) {
+    // current large block is too small. If it is moth-eaten enough to be put
+    // into the small remains bin, do so.
+    if (_current_size < _very_small_bins.maximal_word_size()) {
+      _very_small_bins.put(_current, _current_size);
+      prime_current(); // proceed to next large block.
+      // --- and re-attempt - but only once more. If that fails too, we give up.
+      p = alloc_from_current(requested_word_size);
+    }
+  }
+
+  if (p == NULL) {
+    // Did not work. Check the small bins.
+    if (requested_word_size < _very_small_bins.maximal_word_size()) {
+      block_t* b = _very_small_bins.get(requested_word_size);
+      if (b != NULL) {
+        p = (MetaWord*)b;
+        size_t remaining = b->size - requested_word_size;
+        if (remaining >= _very_small_bins.minimal_word_size()) {
+          MetaWord* q = p + requested_word_size;
+          _very_small_bins.put(q, remaining);
+        }
+      }
+    }
+  }
+
+  if (p != NULL) {
+    _total_word_size.decrement_by(requested_word_size);
+    DEBUG_ONLY(verify();)
+  }
+
+  return p;
+
+}
+
+
+} // namespace metaspace
+
+#endif // SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP