attempted optimization of dbwrapper

it will only work for single-threaded access
This commit is contained in:
Brannon King 2019-08-24 18:44:20 -06:00
parent 4a5d310fd3
commit d96253cd40
3 changed files with 109 additions and 109 deletions

View file

@ -100,10 +100,10 @@ static void SetMaxOpenFiles(leveldb::Options *options) {
static leveldb::Options GetOptions(size_t nCacheSize)
{
leveldb::Options options;
auto write_cache = std::min(nCacheSize / 4, size_t(16) << 20U); // cap write_cache at 16MB (4x default)
auto write_cache = std::min(nCacheSize / 4, size_t(32 * 1024 * 1024)); // cap write_cache
options.block_cache = leveldb::NewLRUCache(nCacheSize - write_cache * 2);
options.write_buffer_size = write_cache; // up to two write buffers may be held in memory simultaneously
options.filter_policy = leveldb::NewBloomFilterPolicy(10);
options.filter_policy = leveldb::NewBloomFilterPolicy(12);
options.compression = leveldb::kNoCompression;
options.info_log = new CBitcoinLevelDBLogger();
if (leveldb::kMajorVersion > 1 || (leveldb::kMajorVersion == 1 && leveldb::kMinorVersion >= 16)) {
@ -116,7 +116,7 @@ static leveldb::Options GetOptions(size_t nCacheSize)
}
CDBWrapper::CDBWrapper(const fs::path& path, size_t nCacheSize, bool fMemory, bool fWipe, bool obfuscate)
: m_name(fs::basename(path))
: m_name(fs::basename(path)), ssKey(SER_DISK, CLIENT_VERSION), ssValue(SER_DISK, CLIENT_VERSION)
{
penv = nullptr;
readoptions.verify_checksums = true;
@ -181,6 +181,11 @@ CDBWrapper::~CDBWrapper()
options.env = nullptr;
}
bool CDBWrapper::Sync() {
CDBBatch batch(*this);
return WriteBatch(batch, true);
}
bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync)
{
const bool log_memory = LogAcceptCategory(BCLog::LEVELDB);

View file

@ -16,9 +16,6 @@
#include <leveldb/db.h>
#include <leveldb/write_batch.h>
static const size_t DBWRAPPER_PREALLOC_KEY_SIZE = 64;
static const size_t DBWRAPPER_PREALLOC_VALUE_SIZE = 1024;
class dbwrapper_error : public std::runtime_error
{
public:
@ -33,87 +30,16 @@ namespace dbwrapper_private {
/** Handle database error by throwing dbwrapper_error exception.
*/
void HandleError(const leveldb::Status& status);
void HandleError(const leveldb::Status& status);
/** Work around circular dependency, as well as for testing in dbwrapper_tests.
* Database obfuscation should be considered an implementation detail of the
* specific database.
*/
const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w);
const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w);
};
/** Batch of changes queued to be written to a CDBWrapper */
class CDBBatch
{
friend class CDBWrapper;
private:
const CDBWrapper &parent;
leveldb::WriteBatch batch;
CDataStream ssKey;
CDataStream ssValue;
size_t size_estimate;
public:
/**
* @param[in] _parent CDBWrapper that this batch is to be submitted to
*/
explicit CDBBatch(const CDBWrapper &_parent) : parent(_parent), ssKey(SER_DISK, CLIENT_VERSION), ssValue(SER_DISK, CLIENT_VERSION), size_estimate(0) { };
void Clear()
{
batch.Clear();
size_estimate = 0;
}
template <typename K, typename V>
void Write(const K& key, const V& value)
{
ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey << key;
leveldb::Slice slKey(ssKey.data(), ssKey.size());
ssValue.reserve(DBWRAPPER_PREALLOC_VALUE_SIZE);
ssValue << value;
ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
leveldb::Slice slValue(ssValue.data(), ssValue.size());
batch.Put(slKey, slValue);
// LevelDB serializes writes as:
// - byte: header
// - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
// - byte[]: key
// - varint: value length
// - byte[]: value
// The formula below assumes the key and value are both less than 16k.
size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
ssKey.clear();
ssValue.clear();
}
template <typename K>
void Erase(const K& key)
{
ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey << key;
leveldb::Slice slKey(ssKey.data(), ssKey.size());
batch.Delete(slKey);
// LevelDB serializes erases as:
// - byte: header
// - varint: key length
// - byte[]: key
// The formula below assumes the key is less than 16kB.
size_estimate += 2 + (slKey.size() > 127) + slKey.size();
ssKey.clear();
}
size_t SizeEstimate() const { return size_estimate; }
};
class CDBIterator
{
private:
@ -127,7 +53,7 @@ public:
* @param[in] _piter The original leveldb iterator.
*/
CDBIterator(const CDBWrapper &_parent, leveldb::Iterator *_piter) :
parent(_parent), piter(_piter) { };
parent(_parent), piter(_piter) { };
~CDBIterator();
bool Valid() const;
@ -135,10 +61,10 @@ public:
void SeekToFirst();
template<typename K> void Seek(const K& key) {
CDataStream ssKey(SER_DISK, CLIENT_VERSION);
ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey << key;
leveldb::Slice slKey(ssKey.data(), ssKey.size());
CDataStream ssKey1(SER_DISK, CLIENT_VERSION);
// ssKey1.reserve(parent.ssKey.capacity());
ssKey1 << key;
leveldb::Slice slKey(ssKey1.data(), ssKey1.size());
piter->Seek(slKey);
}
@ -173,6 +99,8 @@ public:
};
class CDBBatch;
class CDBWrapper
{
friend const std::vector<unsigned char>& dbwrapper_private::GetObfuscateKey(const CDBWrapper &w);
@ -213,6 +141,8 @@ private:
std::vector<unsigned char> CreateObfuscateKey() const;
public:
mutable CDataStream ssKey, ssValue;
/**
* @param[in] path Location in the filesystem where leveldb data will be stored.
* @param[in] nCacheSize Configures various leveldb cache settings.
@ -230,13 +160,12 @@ public:
template <typename K, typename V>
bool Read(const K& key, V& value) const
{
CDataStream ssKey(SER_DISK, CLIENT_VERSION);
ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey << key;
leveldb::Slice slKey(ssKey.data(), ssKey.size());
std::string strValue;
leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
ssKey.clear();
if (!status.ok()) {
if (status.IsNotFound())
return false;
@ -254,23 +183,17 @@ public:
}
template <typename K, typename V>
bool Write(const K& key, const V& value, bool fSync = false)
{
CDBBatch batch(*this);
batch.Write(key, value);
return WriteBatch(batch, fSync);
}
bool Write(const K& key, const V& value, bool fSync = false);
template <typename K>
bool Exists(const K& key) const
{
CDataStream ssKey(SER_DISK, CLIENT_VERSION);
ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey << key;
leveldb::Slice slKey(ssKey.data(), ssKey.size());
std::string strValue;
leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
ssKey.clear();
if (!status.ok()) {
if (status.IsNotFound())
return false;
@ -281,12 +204,7 @@ public:
}
template <typename K>
bool Erase(const K& key, bool fSync = false)
{
CDBBatch batch(*this);
batch.Erase(key);
return WriteBatch(batch, fSync);
}
bool Erase(const K& key, bool fSync = false);
bool WriteBatch(CDBBatch& batch, bool fSync = false);
@ -299,11 +217,7 @@ public:
return true;
}
bool Sync()
{
CDBBatch batch(*this);
return WriteBatch(batch, true);
}
bool Sync();
CDBIterator *NewIterator()
{
@ -319,8 +233,6 @@ public:
size_t EstimateSize(const K& key_begin, const K& key_end) const
{
CDataStream ssKey1(SER_DISK, CLIENT_VERSION), ssKey2(SER_DISK, CLIENT_VERSION);
ssKey1.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey1 << key_begin;
ssKey2 << key_end;
leveldb::Slice slKey1(ssKey1.data(), ssKey1.size());
@ -338,8 +250,8 @@ public:
void CompactRange(const K& key_begin, const K& key_end) const
{
CDataStream ssKey1(SER_DISK, CLIENT_VERSION), ssKey2(SER_DISK, CLIENT_VERSION);
ssKey1.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
ssKey1.reserve(ssKey.capacity());
ssKey2.reserve(ssKey.capacity());
ssKey1 << key_begin;
ssKey2 << key_end;
leveldb::Slice slKey1(ssKey1.data(), ssKey1.size());
@ -349,4 +261,83 @@ public:
};
/** Batch of changes queued to be written to a CDBWrapper */
class CDBBatch
{
friend class CDBWrapper;
const CDBWrapper &parent;
leveldb::WriteBatch batch;
size_t size_estimate;
public:
/**
* @param[in] _parent CDBWrapper that this batch is to be submitted to
*/
explicit CDBBatch(const CDBWrapper &_parent) : parent(_parent), size_estimate(0) { };
void Clear()
{
batch.Clear();
size_estimate = 0;
}
template <typename K, typename V>
void Write(const K& key, const V& value)
{
assert(parent.ssKey.empty());
parent.ssKey << key;
leveldb::Slice slKey(parent.ssKey.data(), parent.ssKey.size());
assert(parent.ssValue.empty());
parent.ssValue << value;
parent.ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
leveldb::Slice slValue(parent.ssValue.data(), parent.ssValue.size());
batch.Put(slKey, slValue);
// LevelDB serializes writes as:
// - byte: header
// - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
// - byte[]: key
// - varint: value length
// - byte[]: value
// The formula below assumes the key and value are both less than 16k.
size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
parent.ssKey.clear();
parent.ssValue.clear();
}
template <typename K>
void Erase(const K& key)
{
parent.ssKey << key;
leveldb::Slice slKey(parent.ssKey.data(), parent.ssKey.size());
batch.Delete(slKey);
// LevelDB serializes erases as:
// - byte: header
// - varint: key length
// - byte[]: key
// The formula below assumes the key is less than 16kB.
size_estimate += 2 + (slKey.size() > 127) + slKey.size();
parent.ssKey.clear();
}
size_t SizeEstimate() const { return size_estimate; }
};
template<typename K>
bool CDBWrapper::Erase(const K &key, bool fSync) {
CDBBatch batch(*this);
batch.Erase(key);
return WriteBatch(batch, fSync);
}
template<typename K, typename V>
bool CDBWrapper::Write(const K &key, const V &value, bool fSync) {
CDBBatch batch(*this);
batch.Write(key, value);
return WriteBatch(batch, fSync);
}
#endif // BITCOIN_DBWRAPPER_H

View file

@ -227,6 +227,10 @@ public:
return (std::string(begin(), end()));
}
std::size_t capacity() const
{
return vch.capacity();
}
//
// Vector subset