src/hotspot/share/gc/g1/g1FullCollector.cpp

*** 39,10 ***
--- 39,11 ---
  #include "gc/g1/g1Policy.hpp"
  #include "gc/g1/g1RegionMarkStatsCache.inline.hpp"
  #include "gc/shared/gcTraceTime.inline.hpp"
  #include "gc/shared/preservedMarks.hpp"
  #include "gc/shared/referenceProcessor.hpp"
+ #include "gc/shared/slidingForwarding.hpp"
  #include "gc/shared/verifyOption.hpp"
  #include "gc/shared/weakProcessor.inline.hpp"
  #include "gc/shared/workerPolicy.hpp"
  #include "logging/log.hpp"
  #include "runtime/handles.inline.hpp"

*** 319,20 ***
  }
  
  void G1FullCollector::phase2_prepare_compaction() {
    GCTraceTime(Info, gc, phases) info("Phase 2: Prepare compaction", scope()->timer());
  
    phase2a_determine_worklists();
  
    bool has_free_compaction_targets = phase2b_forward_oops();
  
    // Try to avoid OOM immediately after Full GC in case there are no free regions
    // left after determining the result locations (i.e. this phase). Prepare to
    // maximally compact the tail regions of the compaction queues serially.
!   if (!has_free_compaction_targets) {
!     phase2c_prepare_serial_compaction();
!   }
  }
  
  void G1FullCollector::phase2a_determine_worklists() {
    GCTraceTime(Debug, gc, phases) debug("Phase 2: Determine work lists", scope()->timer());
  
--- 320,23 ---
  }
  
  void G1FullCollector::phase2_prepare_compaction() {
    GCTraceTime(Info, gc, phases) info("Phase 2: Prepare compaction", scope()->timer());
  
+   _heap->forwarding()->clear();
+ 
    phase2a_determine_worklists();
  
    bool has_free_compaction_targets = phase2b_forward_oops();
  
    // Try to avoid OOM immediately after Full GC in case there are no free regions
    // left after determining the result locations (i.e. this phase). Prepare to
    // maximally compact the tail regions of the compaction queues serially.
!   // TODO: Disabled for now because it violates sliding-forwarding assumption.
!   // if (!has_free_compaction_targets) {
!   //   phase2c_prepare_serial_compaction();
+   // }
  }
  
  void G1FullCollector::phase2a_determine_worklists() {
    GCTraceTime(Debug, gc, phases) debug("Phase 2: Determine work lists", scope()->timer());
  

*** 348,25 ***
  
    return task.has_free_compaction_targets();
  }
  
  void G1FullCollector::phase2c_prepare_serial_compaction() {
!   GCTraceTime(Debug, gc, phases) debug("Phase 2: Prepare serial compaction", scope()->timer());
    // At this point we know that after parallel compaction there will be no
    // completely free regions. That means that the last region of
    // all compaction queues still have data in them. We try to compact
    // these regions in serial to avoid a premature OOM when the mutator wants
    // to allocate the first eden region after gc.
    for (uint i = 0; i < workers(); i++) {
      G1FullGCCompactionPoint* cp = compaction_point(i);
      if (cp->has_regions()) {
        serial_compaction_point()->add(cp->remove_last());
      }
    }
  
    // Update the forwarding information for the regions in the serial
    // compaction point.
    G1FullGCCompactionPoint* cp = serial_compaction_point();
    for (GrowableArrayIterator<HeapRegion*> it = cp->regions()->begin(); it != cp->regions()->end(); ++it) {
      HeapRegion* current = *it;
      if (!cp->is_initialized()) {
        // Initialize the compaction point. Nothing more is needed for the first heap region
--- 352,29 ---
  
    return task.has_free_compaction_targets();
  }
  
  void G1FullCollector::phase2c_prepare_serial_compaction() {
!   ShouldNotReachHere(); // Disabled in Lilliput.
+   //GCTraceTime(Debug, gc, phases) debug("Phase 2: Prepare serial compaction", scope()->timer());
    // At this point we know that after parallel compaction there will be no
    // completely free regions. That means that the last region of
    // all compaction queues still have data in them. We try to compact
    // these regions in serial to avoid a premature OOM when the mutator wants
    // to allocate the first eden region after gc.
+   /*
    for (uint i = 0; i < workers(); i++) {
      G1FullGCCompactionPoint* cp = compaction_point(i);
      if (cp->has_regions()) {
        serial_compaction_point()->add(cp->remove_last());
      }
    }
+   */
  
    // Update the forwarding information for the regions in the serial
    // compaction point.
+   /*
    G1FullGCCompactionPoint* cp = serial_compaction_point();
    for (GrowableArrayIterator<HeapRegion*> it = cp->regions()->begin(); it != cp->regions()->end(); ++it) {
      HeapRegion* current = *it;
      if (!cp->is_initialized()) {
        // Initialize the compaction point. Nothing more is needed for the first heap region

*** 378,10 ***
--- 386,11 ---
        set_compaction_top(current, current->bottom());
        current->apply_to_marked_objects(mark_bitmap(), &re_prepare);
      }
    }
    cp->update();
+   */
  }
  
  void G1FullCollector::phase3_adjust_pointers() {
    // Adjust the pointers to reflect the new locations
    GCTraceTime(Info, gc, phases) info("Phase 3: Adjust pointers", scope()->timer());