Modified: trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheStorage.cpp (182356 => 182357)
--- trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheStorage.cpp 2015-04-05 07:52:14 UTC (rev 182356)
+++ trunk/Source/WebKit2/NetworkProcess/cache/NetworkCacheStorage.cpp 2015-04-05 15:18:47 UTC (rev 182357)
@@ -70,34 +70,75 @@
, m_serialBackgroundIOQueue(WorkQueue::create("com.apple.WebKit.Cache.Storage.serialBackground", WorkQueue::Type::Serial, WorkQueue::QOS::Background))
{
deleteOldVersions();
- initialize();
+ synchronize();
}
-void Storage::initialize()
+void Storage::synchronize()
{
ASSERT(RunLoop::isMain());
+ if (m_synchronizationInProgress || m_shrinkInProgress)
+ return;
+ m_synchronizationInProgress = true;
+
+ LOG(NetworkCacheStorage, "(NetworkProcess) synchronizing cache");
+
StringCapture cachePathCapture(m_directoryPath);
-
backgroundIOQueue().dispatch([this, cachePathCapture] {
String cachePath = cachePathCapture.string();
- traverseCacheFiles(cachePath, [this](const String& fileName, const String& partitionPath) {
+
+ auto filter = std::make_unique<ContentsFilter>();
+ size_t size = 0;
+ unsigned count = 0;
+ traverseCacheFiles(cachePath, [&filter, &size, &count](const String& fileName, const String& partitionPath) {
Key::HashType hash;
if (!Key::stringToHash(fileName, hash))
return;
- unsigned shortHash = Key::toShortHash(hash);
- RunLoop::main().dispatch([this, shortHash] {
- m_contentsFilter.add(shortHash);
- });
auto filePath = WebCore::pathByAppendingComponent(partitionPath, fileName);
long long fileSize = 0;
WebCore::getFileSize(filePath, fileSize);
- m_approximateSize += fileSize;
+ if (!fileSize)
+ return;
+ filter->add(Key::toShortHash(hash));
+ size += fileSize;
+ ++count;
});
- m_hasPopulatedContentsFilter = true;
+
+ auto* filterPtr = filter.release();
+ RunLoop::main().dispatch([this, filterPtr, size] {
+ auto filter = std::unique_ptr<ContentsFilter>(filterPtr);
+
+ for (auto hash : m_contentsFilterHashesAddedDuringSynchronization)
+ filter->add(hash);
+ m_contentsFilterHashesAddedDuringSynchronization.clear();
+
+ m_contentsFilter = WTF::move(filter);
+ m_approximateSize = size;
+ m_synchronizationInProgress = false;
+ });
+
+ LOG(NetworkCacheStorage, "(NetworkProcess) cache synchronization completed approximateSize=%zu count=%d", size, count);
});
}
+void Storage::addToContentsFilter(const Key& key)
+{
+ ASSERT(RunLoop::isMain());
+
+ if (m_contentsFilter)
+ m_contentsFilter->add(key.shortHash());
+
+ // If we get new entries during filter synchronization take care to add them to the new filter as well.
+ if (m_synchronizationInProgress)
+ m_contentsFilterHashesAddedDuringSynchronization.append(key.shortHash());
+}
+
+bool Storage::mayContain(const Key& key) const
+{
+ ASSERT(RunLoop::isMain());
+ return !m_contentsFilter || m_contentsFilter->mayContain(key.shortHash());
+}
+
static String directoryPathForKey(const Key& key, const String& cachePath)
{
ASSERT(!key.partition().isEmpty());
@@ -288,12 +329,10 @@
{
ASSERT(RunLoop::isMain());
- // For simplicity we don't reduce m_approximateSize on removals.
- // The next cache shrink will update the size.
+ // We can't remove the key from the Bloom filter (but some false positives are expected anyway).
+ // For simplicity we also don't reduce m_approximateSize on removals.
+ // The next synchronization will update everything.
- if (m_contentsFilter.mayContain(key.shortHash()))
- m_contentsFilter.remove(key.shortHash());
-
StringCapture filePathCapture(filePathForKey(key, m_directoryPath));
serialBackgroundIOQueue().dispatch([this, filePathCapture] {
WebCore::deleteFile(filePathCapture.string());
@@ -385,7 +424,7 @@
return;
}
- if (!cacheMayContain(key.shortHash())) {
+ if (!mayContain(key)) {
completionHandler(nullptr);
return;
}
@@ -412,7 +451,7 @@
m_pendingWriteOperations.append(new WriteOperation { record, { }, WTF::move(completionHandler) });
// Add key to the filter already here as we do lookups from the pending operations too.
- m_contentsFilter.add(record.key.shortHash());
+ addToContentsFilter(record.key);
dispatchPendingWriteOperations();
}
@@ -479,7 +518,7 @@
auto& write = *writeOperation;
m_activeWriteOperations.add(WTF::move(writeOperation));
- if (write.existingRecord && cacheMayContain(write.record.key.shortHash())) {
+ if (write.existingRecord && mayContain(write.record.key)) {
dispatchHeaderWriteOperation(write);
continue;
}
@@ -492,8 +531,8 @@
ASSERT(RunLoop::isMain());
ASSERT(m_activeWriteOperations.contains(&write));
- if (!m_contentsFilter.mayContain(write.record.key.shortHash()))
- m_contentsFilter.add(write.record.key.shortHash());
+ // This was added already when starting the store but filter might have been wiped.
+ addToContentsFilter(write.record.key);
StringCapture cachePathCapture(m_directoryPath);
backgroundIOQueue().dispatch([this, &write, cachePathCapture] {
@@ -505,14 +544,10 @@
size_t bodyOffset = encodedHeader.size();
channel->write(0, headerAndBodyData, [this, &write, bodyOffset, fd](int error) {
- LOG(NetworkCacheStorage, "(NetworkProcess) write complete error=%d", error);
- if (error) {
- if (m_contentsFilter.mayContain(write.record.key.shortHash()))
- m_contentsFilter.remove(write.record.key.shortHash());
- }
size_t bodySize = write.record.body.size();
size_t totalSize = bodyOffset + bodySize;
+ // On error the entry still stays in the contents filter until next synchronization.
m_approximateSize += totalSize;
bool shouldMapBody = !error && bodySize >= pageSize();
@@ -523,6 +558,8 @@
ASSERT(m_activeWriteOperations.contains(&write));
m_activeWriteOperations.remove(&write);
dispatchPendingWriteOperations();
+
+ LOG(NetworkCacheStorage, "(NetworkProcess) write complete error=%d", error);
});
});
@@ -534,7 +571,7 @@
ASSERT(RunLoop::isMain());
ASSERT(write.existingRecord);
ASSERT(m_activeWriteOperations.contains(&write));
- ASSERT(cacheMayContain(write.record.key.shortHash()));
+ ASSERT(mayContain(write.record.key));
// Try to update the header of an existing entry.
StringCapture cachePathCapture(m_directoryPath);
@@ -570,6 +607,16 @@
void Storage::setMaximumSize(size_t size)
{
ASSERT(RunLoop::isMain());
+
+#if !ASSERT_DISABLED
+ const size_t assumedAverageRecordSize = 50 << 20;
+ size_t maximumRecordCount = size / assumedAverageRecordSize;
+ // ~10 bits per element are required for <1% false positive rate.
+ size_t effectiveBloomFilterCapacity = ContentsFilter::tableSize / 10;
+ // If this gets hit it might be time to increase the filter size.
+ ASSERT(maximumRecordCount < effectiveBloomFilterCapacity);
+#endif
+
m_maximumSize = size;
shrinkIfNeeded();
@@ -580,7 +627,8 @@
ASSERT(RunLoop::isMain());
LOG(NetworkCacheStorage, "(NetworkProcess) clearing cache");
- m_contentsFilter.clear();
+ if (m_contentsFilter)
+ m_contentsFilter->clear();
m_approximateSize = 0;
StringCapture directoryPathCapture(m_directoryPath);
@@ -629,20 +677,24 @@
{
ASSERT(RunLoop::isMain());
- if (m_approximateSize <= m_maximumSize)
+ if (m_approximateSize > m_maximumSize)
+ shrink();
+}
+
+void Storage::shrink()
+{
+ ASSERT(RunLoop::isMain());
+
+ if (m_shrinkInProgress || m_synchronizationInProgress)
return;
- if (m_shrinkInProgress)
- return;
m_shrinkInProgress = true;
LOG(NetworkCacheStorage, "(NetworkProcess) shrinking cache approximateSize=%zu, m_maximumSize=%zu", static_cast<size_t>(m_approximateSize), m_maximumSize);
- m_approximateSize = 0;
-
StringCapture cachePathCapture(m_directoryPath);
backgroundIOQueue().dispatch([this, cachePathCapture] {
String cachePath = cachePathCapture.string();
- traverseCacheFiles(cachePath, [this](const String& fileName, const String& partitionPath) {
+ traverseCacheFiles(cachePath, [](const String& fileName, const String& partitionPath) {
auto filePath = WebCore::pathByAppendingComponent(partitionPath, fileName);
auto times = fileTimes(filePath);
@@ -651,22 +703,8 @@
LOG(NetworkCacheStorage, "Deletion probability=%f shouldDelete=%d", probability, shouldDelete);
- if (!shouldDelete) {
- long long fileSize = 0;
- WebCore::getFileSize(filePath, fileSize);
- m_approximateSize += fileSize;
- return;
- }
-
- WebCore::deleteFile(filePath);
- Key::HashType hash;
- if (!Key::stringToHash(fileName, hash))
- return;
- unsigned shortHash = Key::toShortHash(hash);
- RunLoop::main().dispatch([this, shortHash] {
- if (m_contentsFilter.mayContain(shortHash))
- m_contentsFilter.remove(shortHash);
- });
+ if (shouldDelete)
+ WebCore::deleteFile(filePath);
});
// Let system figure out if they are really empty.
@@ -675,9 +713,13 @@
WebCore::deleteEmptyDirectory(partitionPath);
});
- m_shrinkInProgress = false;
+ RunLoop::main().dispatch([this] {
+ m_shrinkInProgress = false;
+ // We could synchronize during the shrink traversal. However this is fast and it is better to have just one code path.
+ synchronize();
+ });
- LOG(NetworkCacheStorage, "(NetworkProcess) cache shrink completed approximateSize=%zu", static_cast<size_t>(m_approximateSize));
+ LOG(NetworkCacheStorage, "(NetworkProcess) cache shrink completed");
});
}
