void MemoryCache::dumpLRULists(bool includeLive) const
{
printf("LRU-SP lists in eviction order (Kilobytes decoded, Kilobytes encoded, Access count, Referenced, isPurgeable, wasPurged):\n");
int size = m_allResources.size();
for (int i = size - 1; i >= 0; i--) {
printf("\n\nList %d: ", i);
Resource* current = m_allResources[i].m_tail;
while (current) {
Resource* prev = current->m_prevInAllResourcesList;
if (includeLive || !current->hasClients())
printf("(%.1fK, %.1fK, %uA, %dR, %d, %d); ", current->decodedSize() / 1024.0f, (current->encodedSize() + current->overheadSize()) / 1024.0f, current->accessCount(), current->hasClients(), current->isPurgeable(), current->wasPurged());
current = prev;
}
}
}
void MemoryCache::pruneLiveResources()
{
unsigned capacity = liveCapacity();
if (!m_liveSize || (capacity && m_liveSize <= capacity))
return;
unsigned targetSize = static_cast<unsigned>(capacity * cTargetPrunePercentage); // Cut by a percentage to avoid immediately pruning again.
double currentTime = FrameView::currentPaintTimeStamp();
if (!currentTime) // In case prune is called directly, outside of a Frame paint.
currentTime = WTF::currentTime();
// Destroy any decoded data in live objects that we can.
// Start from the tail, since this is the lowest priority
// and least recently accessed of the objects.
// The list might not be sorted by the m_lastDecodedAccessTime. The impact
// of this weaker invariant is minor as the below if statement to check the
// elapsedTime will evaluate to false as the currentTime will be a lot
// greater than the current->m_lastDecodedAccessTime.
// For more details see: https://bugs.webkit.org/show_bug.cgi?id=30209
// Start pruning from the lowest priority list.
for (int priority = Resource::CacheLiveResourcePriorityLow; priority <= Resource::CacheLiveResourcePriorityHigh; ++priority) {
Resource* current = m_liveDecodedResources[priority].m_tail;
while (current) {
Resource* prev = current->m_prevInLiveResourcesList;
ASSERT(current->hasClients());
if (current->isLoaded() && current->decodedSize()) {
// Check to see if the remaining resources are too new to prune.
double elapsedTime = currentTime - current->m_lastDecodedAccessTime;
if (elapsedTime < m_delayBeforeLiveDecodedPrune)
return;
// Destroy our decoded data. This will remove us from
// m_liveDecodedResources, and possibly move us to a different LRU
// list in m_allResources.
current->destroyDecodedData();
if (targetSize && m_liveSize <= targetSize)
return;
}
current = prev;
}
}
}
