void CopiedSpace::didStartFullCollection()
{
    ASSERT(heap()->operationInProgress() == FullCollection);
    ASSERT(m_oldGen.fromSpace->isEmpty());
    ASSERT(m_newGen.fromSpace->isEmpty());

#ifndef NDEBUG
    for (CopiedBlock* block = m_newGen.toSpace->head(); block; block = block->next())
        ASSERT(!block->liveBytes());

    for (CopiedBlock* block = m_newGen.oversizeBlocks.head(); block; block = block->next())
        ASSERT(!block->liveBytes());
#endif

    for (CopiedBlock* block = m_oldGen.toSpace->head(); block; block = block->next())
        block->didSurviveGC();

    for (CopiedBlock* block = m_oldGen.oversizeBlocks.head(); block; block = block->next())
        block->didSurviveGC();
}
Пример #2
0
void CopiedSpace::startedCopying()
{
    std::swap(m_fromSpace, m_toSpace);

    m_blockFilter.reset();
    m_allocator.resetCurrentBlock();

    CopiedBlock* next = 0;
    size_t totalLiveBytes = 0;
    size_t totalUsableBytes = 0;
    for (CopiedBlock* block = m_fromSpace->head(); block; block = next) {
        next = block->next();
        if (!block->isPinned() && block->canBeRecycled()) {
            recycleEvacuatedBlock(block);
            continue;
        }
        totalLiveBytes += block->liveBytes();
        totalUsableBytes += block->payloadCapacity();
    }

    CopiedBlock* block = m_oversizeBlocks.head();
    while (block) {
        CopiedBlock* next = block->next();
        if (block->isPinned()) {
            m_blockFilter.add(reinterpret_cast<Bits>(block));
            totalLiveBytes += block->payloadCapacity();
            totalUsableBytes += block->payloadCapacity();
            block->didSurviveGC();
        } else {
            m_oversizeBlocks.remove(block);
            m_blockSet.remove(block);
            m_heap->blockAllocator().deallocateCustomSize(CopiedBlock::destroy(block));
        } 
        block = next;
    }

    double markedSpaceBytes = m_heap->objectSpace().capacity();
    double totalFragmentation = ((double)totalLiveBytes + markedSpaceBytes) / ((double)totalUsableBytes + markedSpaceBytes);
    m_shouldDoCopyPhase = totalFragmentation <= Options::minHeapUtilization();
    if (!m_shouldDoCopyPhase)
        return;

    ASSERT(m_shouldDoCopyPhase);
    ASSERT(!m_inCopyingPhase);
    ASSERT(!m_numberOfLoanedBlocks);
    m_inCopyingPhase = true;
}