Mark pages created during bootstrapping as never-evacuate.

src/heap/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/base/atomicops.h"
 #include "src/base/bits.h"
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
@@ skipping 224 matching lines @@
 }
 
 
 void MarkCompactCollector::TearDown() {
   AbortCompaction();
   delete marking_deque_memory_;
 }
 
 
 void MarkCompactCollector::AddEvacuationCandidate(Page* p) {
+  if (p->NeverEvacuate()) return;

[Hannes Payer (out of office), 2015/02/12 13:20:23]

Dont' make the page an evacuation candidate. Please DCHECK here that is
compactable here.

   p->MarkEvacuationCandidate();
   evacuation_candidates_.Add(p);
 }
 
 
 static void TraceFragmentation(PagedSpace* space) {
   int number_of_pages = space->CountTotalPages();
   intptr_t reserved = (number_of_pages * space->AreaSize());
   intptr_t free = reserved - space->SizeOfObjects();
   PrintF("[%s]: %d pages, %d (%.1f%%) free\n",
@@ skipping 456 matching lines @@
   Candidate candidates[kMaxMaxEvacuationCandidates];
 
   max_evacuation_candidates =
       Min(kMaxMaxEvacuationCandidates, max_evacuation_candidates);
 
   int count = 0;
   int fragmentation = 0;
   Candidate* least = NULL;
 
   PageIterator it(space);
-  if (it.has_next()) it.next();  // Never compact the first page.
-
   while (it.has_next()) {
     Page* p = it.next();
     p->ClearEvacuationCandidate();
 

[Hannes Payer (out of office), 2015/02/12 13:20:23]

If NeverEvacuate() is set, ignore the page.

     if (FLAG_stress_compaction) {
       unsigned int counter = space->heap()->ms_count();
       uintptr_t page_number = reinterpret_cast<uintptr_t>(p) >> kPageSizeBits;
       if ((counter & 1) == (page_number & 1)) fragmentation = 1;
     } else if (mode == REDUCE_MEMORY_FOOTPRINT) {
       // Don't try to release too many pages.
       if (estimated_release >= over_reserved) {
         continue;
       }
 
@@ skipping 3685 matching lines @@
   SlotsBuffer* buffer = *buffer_address;
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 }
 }  // namespace v8::internal