Index: content/browser/indexed_db/leveldb/leveldb_database.h |
diff --git a/content/browser/indexed_db/leveldb/leveldb_database.h b/content/browser/indexed_db/leveldb/leveldb_database.h |
index cdcabb54647c83c9d2f56690e2a84ba2fecd87c9..ab3800e4ac3f9fdd7677990a3b9cc6b400e71758 100644 |
--- a/content/browser/indexed_db/leveldb/leveldb_database.h |
+++ b/content/browser/indexed_db/leveldb/leveldb_database.h |
@@ -8,6 +8,7 @@ |
#include <memory> |
#include <string> |
+#include "base/containers/mru_cache.h" |
#include "base/files/file_path.h" |
#include "base/macros.h" |
#include "base/strings/string16.h" |
@@ -21,6 +22,7 @@ namespace leveldb { |
class Comparator; |
class DB; |
class FilterPolicy; |
+class Iterator; |
class Env; |
class Snapshot; |
} |
@@ -58,6 +60,10 @@ class CONTENT_EXPORT LevelDBLock { |
class CONTENT_EXPORT LevelDBDatabase |
: public base::trace_event::MemoryDumpProvider { |
public: |
+ // Necessary because every iterator hangs onto leveldb blocks which can be |
+ // large. See https://crbug/696055. |
+ static const size_t kDefaultMaxOpenIteratorsPerDatabase = 50; |
+ |
class ComparatorAdapter : public leveldb::Comparator { |
public: |
explicit ComparatorAdapter(const LevelDBComparator* comparator); |
@@ -75,10 +81,13 @@ class CONTENT_EXPORT LevelDBDatabase |
const LevelDBComparator* comparator_; |
}; |
+ // |max_open_cursors| cannot be 0. |
static leveldb::Status Open(const base::FilePath& file_name, |
const LevelDBComparator* comparator, |
+ size_t max_open_cursors, |
std::unique_ptr<LevelDBDatabase>* db, |
bool* is_disk_full = 0); |
+ |
static std::unique_ptr<LevelDBDatabase> OpenInMemory( |
const LevelDBComparator* comparator); |
static leveldb::Status Destroy(const base::FilePath& file_name); |
@@ -103,10 +112,17 @@ class CONTENT_EXPORT LevelDBDatabase |
base::trace_event::ProcessMemoryDump* pmd) override; |
protected: |
- LevelDBDatabase(); |
+ LevelDBDatabase(size_t max_open_iterators); |
private: |
friend class LevelDBSnapshot; |
+ friend class LevelDBIteratorImpl; |
+ |
+ // Methods for iterator pooling. |
+ std::unique_ptr<leveldb::Iterator> CreateLevelDBIterator( |
+ const leveldb::Snapshot*); |
+ void OnIteratorUsed(LevelDBIterator*); |
+ void OnIteratorDestroyed(LevelDBIterator*); |
void CloseDatabase(); |
@@ -115,6 +131,31 @@ class CONTENT_EXPORT LevelDBDatabase |
std::unique_ptr<leveldb::DB> db_; |
std::unique_ptr<const leveldb::FilterPolicy> filter_policy_; |
const LevelDBComparator* comparator_; |
+ |
+ struct DetachIteratorOnDestruct { |
+ DetachIteratorOnDestruct() {} |
+ explicit DetachIteratorOnDestruct(LevelDBIterator* it) : it_(it) {} |
+ DetachIteratorOnDestruct(DetachIteratorOnDestruct&& that) { |
+ it_ = that.it_; |
+ that.it_ = nullptr; |
+ } |
+ ~DetachIteratorOnDestruct(); |
+ |
+ private: |
+ LevelDBIterator* it_ = nullptr; |
+ |
+ DISALLOW_COPY_AND_ASSIGN(DetachIteratorOnDestruct); |
+ }; |
+ |
+ // Despite the type name, this object uses LRU eviction. |
+ size_t lru_max_size_ = 0; |
+ base::HashingMRUCache<LevelDBIterator*, DetachIteratorOnDestruct> |
+ iterator_lru_; |
+ |
+ // Recorded for UMA reporting. |
+ uint32_t num_iterators_ = 0; |
+ uint32_t max_iterators_ = 0; |
+ |
std::string file_name_for_tracing; |
}; |