Remove eager sweeping for lazy swept spaces. Try to find in SlowAllocateRaw a bounded number of tim…

src/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3507 matching lines @@
 void MarkCompactCollector::SweepSpace(PagedSpace* space, SweeperType sweeper) {
   space->set_was_swept_conservatively(sweeper == CONSERVATIVE ||
                                       sweeper == LAZY_CONSERVATIVE);
 
   space->ClearStats();
 
   PageIterator it(space);
 
   intptr_t freed_bytes = 0;
   int pages_swept = 0;
-  intptr_t newspace_size = space->heap()->new_space()->Size();
   bool lazy_sweeping_active = false;
   bool unused_page_present = false;
 
   while (it.has_next()) {
     Page* p = it.next();
 
     // Clear sweeping flags indicating that marking bits are still intact.
     p->ClearSweptPrecisely();
     p->ClearSweptConservatively();
 
@@ skipping 42 matching lines @@
         pages_swept++;
         break;
       }
       case LAZY_CONSERVATIVE: {
         if (FLAG_gc_verbose) {
           PrintF("Sweeping 0x%" V8PRIxPTR " conservatively as needed.\n",
                  reinterpret_cast<intptr_t>(p));
         }
         freed_bytes += SweepConservatively(space, p);
         pages_swept++;
-        if (freed_bytes > 2 * newspace_size) {
-          space->SetPagesToSweep(p->next_page());
-          lazy_sweeping_active = true;
-        } else {
-          if (FLAG_gc_verbose) {
-            PrintF("Only %" V8PRIdPTR " bytes freed.  Still sweeping.\n",
-                   freed_bytes);
-          }
-        }
+        space->SetPagesToSweep(p->next_page());
+        lazy_sweeping_active = true;
         break;
       }
       case PRECISE: {
         if (FLAG_gc_verbose) {
           PrintF("Sweeping 0x%" V8PRIxPTR " precisely.\n",
                  reinterpret_cast<intptr_t>(p));
         }
         if (space->identity() == CODE_SPACE) {
           SweepPrecisely<SWEEP_ONLY, REBUILD_SKIP_LIST>(space, p, NULL);
         } else {
@@ skipping 243 matching lines @@
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 
 
 } }  // namespace v8::internal