src/share/vm/gc_implementation/shared/plab.cpp

*** 82,95 ****
      result += invalidate();
    }
    return result;
  }
  
! // Compute desired plab size and latch result for later
  // use. This should be called once at the end of parallel
  // scavenge; it clears the sensor accumulators.
! void PLABStats::adjust_desired_plab_sz(uint no_of_gc_workers) {
    assert(ResizePLAB, "Not set");
  
    assert(is_object_aligned(max_size()) && min_size() <= max_size(),
           "PLAB clipping computation may be incorrect");
  
--- 82,102 ----
      result += invalidate();
    }
    return result;
  }
  
! // Calculates plab size for current number of gc worker threads.
! size_t PLABStats::desired_plab_sz(uint no_of_gc_workers) {
!   assert(no_of_gc_workers > 0, "Number of GC workers should be larger than zero");
! 
!   return align_object_size(_desired_net_plab_sz / MAX2(no_of_gc_workers, 1U));
! }
! 
! // Compute desired plab size for one gc worker thread and latch result for later
  // use. This should be called once at the end of parallel
  // scavenge; it clears the sensor accumulators.
! void PLABStats::adjust_desired_plab_sz() {
    assert(ResizePLAB, "Not set");
  
    assert(is_object_aligned(max_size()) && min_size() <= max_size(),
           "PLAB clipping computation may be incorrect");
  
*** 107,128 ****
    size_t target_refills = (size_t)((wasted_frac * TargetSurvivorRatio) / TargetPLABWastePct);
    if (target_refills == 0) {
      target_refills = 1;
    }
    size_t used = _allocated - _wasted - _unused;
!   size_t recent_plab_sz = used / (target_refills * no_of_gc_workers);
    // Take historical weighted average
    _filter.sample(recent_plab_sz);
    // Clip from above and below, and align to object boundary
    size_t new_plab_sz = MAX2(min_size(), (size_t)_filter.average());
    new_plab_sz = MIN2(max_size(), new_plab_sz);
    new_plab_sz = align_object_size(new_plab_sz);
    // Latch the result
    if (PrintPLAB) {
      gclog_or_tty->print(" (plab_sz = " SIZE_FORMAT" desired_plab_sz = " SIZE_FORMAT") ", recent_plab_sz, new_plab_sz);
    }
!   _desired_plab_sz = new_plab_sz;
  
    reset();
  }
  
  #ifndef PRODUCT
--- 114,136 ----
    size_t target_refills = (size_t)((wasted_frac * TargetSurvivorRatio) / TargetPLABWastePct);
    if (target_refills == 0) {
      target_refills = 1;
    }
    size_t used = _allocated - _wasted - _unused;
!   // Assumed to have 1 gc worker thread
!   size_t recent_plab_sz = used / target_refills;
    // Take historical weighted average
    _filter.sample(recent_plab_sz);
    // Clip from above and below, and align to object boundary
    size_t new_plab_sz = MAX2(min_size(), (size_t)_filter.average());
    new_plab_sz = MIN2(max_size(), new_plab_sz);
    new_plab_sz = align_object_size(new_plab_sz);
    // Latch the result
    if (PrintPLAB) {
      gclog_or_tty->print(" (plab_sz = " SIZE_FORMAT" desired_plab_sz = " SIZE_FORMAT") ", recent_plab_sz, new_plab_sz);
    }
!   _desired_net_plab_sz = new_plab_sz;
  
    reset();
  }
  
  #ifndef PRODUCT