diff options
Diffstat (limited to 'src/leveldb/util')
-rw-r--r-- | src/leveldb/util/arena.cc | 6 | ||||
-rw-r--r-- | src/leveldb/util/arena.h | 10 | ||||
-rw-r--r-- | src/leveldb/util/bloom.cc | 2 | ||||
-rw-r--r-- | src/leveldb/util/bloom_test.cc | 3 | ||||
-rw-r--r-- | src/leveldb/util/cache.cc | 136 | ||||
-rw-r--r-- | src/leveldb/util/cache_test.cc | 42 | ||||
-rw-r--r-- | src/leveldb/util/env.cc | 4 | ||||
-rw-r--r-- | src/leveldb/util/env_posix.cc | 13 | ||||
-rw-r--r-- | src/leveldb/util/env_win.cc | 37 | ||||
-rw-r--r-- | src/leveldb/util/options.cc | 2 | ||||
-rw-r--r-- | src/leveldb/util/testutil.h | 10 |
11 files changed, 218 insertions, 47 deletions
diff --git a/src/leveldb/util/arena.cc b/src/leveldb/util/arena.cc index 9367f71492..74078213ee 100644 --- a/src/leveldb/util/arena.cc +++ b/src/leveldb/util/arena.cc @@ -9,8 +9,7 @@ namespace leveldb { static const int kBlockSize = 4096; -Arena::Arena() { - blocks_memory_ = 0; +Arena::Arena() : memory_usage_(0) { alloc_ptr_ = NULL; // First allocation will allocate a block alloc_bytes_remaining_ = 0; } @@ -60,8 +59,9 @@ char* Arena::AllocateAligned(size_t bytes) { char* Arena::AllocateNewBlock(size_t block_bytes) { char* result = new char[block_bytes]; - blocks_memory_ += block_bytes; blocks_.push_back(result); + memory_usage_.NoBarrier_Store( + reinterpret_cast<void*>(MemoryUsage() + block_bytes + sizeof(char*))); return result; } diff --git a/src/leveldb/util/arena.h b/src/leveldb/util/arena.h index 73bbf1cb9b..48bab33741 100644 --- a/src/leveldb/util/arena.h +++ b/src/leveldb/util/arena.h @@ -9,6 +9,7 @@ #include <assert.h> #include <stddef.h> #include <stdint.h> +#include "port/port.h" namespace leveldb { @@ -24,10 +25,9 @@ class Arena { char* AllocateAligned(size_t bytes); // Returns an estimate of the total memory usage of data allocated - // by the arena (including space allocated but not yet used for user - // allocations). + // by the arena. size_t MemoryUsage() const { - return blocks_memory_ + blocks_.capacity() * sizeof(char*); + return reinterpret_cast<uintptr_t>(memory_usage_.NoBarrier_Load()); } private: @@ -41,8 +41,8 @@ class Arena { // Array of new[] allocated memory blocks std::vector<char*> blocks_; - // Bytes of memory in blocks allocated so far - size_t blocks_memory_; + // Total memory usage of the arena. + port::AtomicPointer memory_usage_; // No copying allowed Arena(const Arena&); diff --git a/src/leveldb/util/bloom.cc b/src/leveldb/util/bloom.cc index a27a2ace28..bf3e4ca6e9 100644 --- a/src/leveldb/util/bloom.cc +++ b/src/leveldb/util/bloom.cc @@ -47,7 +47,7 @@ class BloomFilterPolicy : public FilterPolicy { dst->resize(init_size + bytes, 0); dst->push_back(static_cast<char>(k_)); // Remember # of probes in filter char* array = &(*dst)[init_size]; - for (size_t i = 0; i < n; i++) { + for (int i = 0; i < n; i++) { // Use double-hashing to generate a sequence of hash values. // See analysis in [Kirsch,Mitzenmacher 2006]. uint32_t h = BloomHash(keys[i]); diff --git a/src/leveldb/util/bloom_test.cc b/src/leveldb/util/bloom_test.cc index 77fb1b3159..1b87a2be3f 100644 --- a/src/leveldb/util/bloom_test.cc +++ b/src/leveldb/util/bloom_test.cc @@ -46,7 +46,8 @@ class BloomTest { key_slices.push_back(Slice(keys_[i])); } filter_.clear(); - policy_->CreateFilter(&key_slices[0], key_slices.size(), &filter_); + policy_->CreateFilter(&key_slices[0], static_cast<int>(key_slices.size()), + &filter_); keys_.clear(); if (kVerbose >= 2) DumpFilter(); } diff --git a/src/leveldb/util/cache.cc b/src/leveldb/util/cache.cc index 8b197bc02a..ce46886171 100644 --- a/src/leveldb/util/cache.cc +++ b/src/leveldb/util/cache.cc @@ -19,6 +19,23 @@ Cache::~Cache() { namespace { // LRU cache implementation +// +// Cache entries have an "in_cache" boolean indicating whether the cache has a +// reference on the entry. The only ways that this can become false without the +// entry being passed to its "deleter" are via Erase(), via Insert() when +// an element with a duplicate key is inserted, or on destruction of the cache. +// +// The cache keeps two linked lists of items in the cache. All items in the +// cache are in one list or the other, and never both. Items still referenced +// by clients but erased from the cache are in neither list. The lists are: +// - in-use: contains the items currently referenced by clients, in no +// particular order. (This list is used for invariant checking. If we +// removed the check, elements that would otherwise be on this list could be +// left as disconnected singleton lists.) +// - LRU: contains the items not currently referenced by clients, in LRU order +// Elements are moved between these lists by the Ref() and Unref() methods, +// when they detect an element in the cache acquiring or losing its only +// external reference. // An entry is a variable length heap-allocated structure. Entries // are kept in a circular doubly linked list ordered by access time. @@ -30,7 +47,8 @@ struct LRUHandle { LRUHandle* prev; size_t charge; // TODO(opt): Only allow uint32_t? size_t key_length; - uint32_t refs; + bool in_cache; // Whether entry is in the cache. + uint32_t refs; // References, including cache reference, if present. uint32_t hash; // Hash of key(); used for fast sharding and comparisons char key_data[1]; // Beginning of key @@ -147,49 +165,77 @@ class LRUCache { Cache::Handle* Lookup(const Slice& key, uint32_t hash); void Release(Cache::Handle* handle); void Erase(const Slice& key, uint32_t hash); + void Prune(); + size_t TotalCharge() const { + MutexLock l(&mutex_); + return usage_; + } private: void LRU_Remove(LRUHandle* e); - void LRU_Append(LRUHandle* e); + void LRU_Append(LRUHandle*list, LRUHandle* e); + void Ref(LRUHandle* e); void Unref(LRUHandle* e); + bool FinishErase(LRUHandle* e); // Initialized before use. size_t capacity_; // mutex_ protects the following state. - port::Mutex mutex_; + mutable port::Mutex mutex_; size_t usage_; // Dummy head of LRU list. // lru.prev is newest entry, lru.next is oldest entry. + // Entries have refs==1 and in_cache==true. LRUHandle lru_; + // Dummy head of in-use list. + // Entries are in use by clients, and have refs >= 2 and in_cache==true. + LRUHandle in_use_; + HandleTable table_; }; LRUCache::LRUCache() : usage_(0) { - // Make empty circular linked list + // Make empty circular linked lists. lru_.next = &lru_; lru_.prev = &lru_; + in_use_.next = &in_use_; + in_use_.prev = &in_use_; } LRUCache::~LRUCache() { + assert(in_use_.next == &in_use_); // Error if caller has an unreleased handle for (LRUHandle* e = lru_.next; e != &lru_; ) { LRUHandle* next = e->next; - assert(e->refs == 1); // Error if caller has an unreleased handle + assert(e->in_cache); + e->in_cache = false; + assert(e->refs == 1); // Invariant of lru_ list. Unref(e); e = next; } } +void LRUCache::Ref(LRUHandle* e) { + if (e->refs == 1 && e->in_cache) { // If on lru_ list, move to in_use_ list. + LRU_Remove(e); + LRU_Append(&in_use_, e); + } + e->refs++; +} + void LRUCache::Unref(LRUHandle* e) { assert(e->refs > 0); e->refs--; - if (e->refs <= 0) { - usage_ -= e->charge; + if (e->refs == 0) { // Deallocate. + assert(!e->in_cache); (*e->deleter)(e->key(), e->value); free(e); + } else if (e->in_cache && e->refs == 1) { // No longer in use; move to lru_ list. + LRU_Remove(e); + LRU_Append(&lru_, e); } } @@ -198,10 +244,10 @@ void LRUCache::LRU_Remove(LRUHandle* e) { e->prev->next = e->next; } -void LRUCache::LRU_Append(LRUHandle* e) { - // Make "e" newest entry by inserting just before lru_ - e->next = &lru_; - e->prev = lru_.prev; +void LRUCache::LRU_Append(LRUHandle* list, LRUHandle* e) { + // Make "e" newest entry by inserting just before *list + e->next = list; + e->prev = list->prev; e->prev->next = e; e->next->prev = e; } @@ -210,9 +256,7 @@ Cache::Handle* LRUCache::Lookup(const Slice& key, uint32_t hash) { MutexLock l(&mutex_); LRUHandle* e = table_.Lookup(key, hash); if (e != NULL) { - e->refs++; - LRU_Remove(e); - LRU_Append(e); + Ref(e); } return reinterpret_cast<Cache::Handle*>(e); } @@ -234,34 +278,58 @@ Cache::Handle* LRUCache::Insert( e->charge = charge; e->key_length = key.size(); e->hash = hash; - e->refs = 2; // One from LRUCache, one for the returned handle + e->in_cache = false; + e->refs = 1; // for the returned handle. memcpy(e->key_data, key.data(), key.size()); - LRU_Append(e); - usage_ += charge; - LRUHandle* old = table_.Insert(e); - if (old != NULL) { - LRU_Remove(old); - Unref(old); - } + if (capacity_ > 0) { + e->refs++; // for the cache's reference. + e->in_cache = true; + LRU_Append(&in_use_, e); + usage_ += charge; + FinishErase(table_.Insert(e)); + } // else don't cache. (Tests use capacity_==0 to turn off caching.) while (usage_ > capacity_ && lru_.next != &lru_) { LRUHandle* old = lru_.next; - LRU_Remove(old); - table_.Remove(old->key(), old->hash); - Unref(old); + assert(old->refs == 1); + bool erased = FinishErase(table_.Remove(old->key(), old->hash)); + if (!erased) { // to avoid unused variable when compiled NDEBUG + assert(erased); + } } return reinterpret_cast<Cache::Handle*>(e); } -void LRUCache::Erase(const Slice& key, uint32_t hash) { - MutexLock l(&mutex_); - LRUHandle* e = table_.Remove(key, hash); +// If e != NULL, finish removing *e from the cache; it has already been removed +// from the hash table. Return whether e != NULL. Requires mutex_ held. +bool LRUCache::FinishErase(LRUHandle* e) { if (e != NULL) { + assert(e->in_cache); LRU_Remove(e); + e->in_cache = false; + usage_ -= e->charge; Unref(e); } + return e != NULL; +} + +void LRUCache::Erase(const Slice& key, uint32_t hash) { + MutexLock l(&mutex_); + FinishErase(table_.Remove(key, hash)); +} + +void LRUCache::Prune() { + MutexLock l(&mutex_); + while (lru_.next != &lru_) { + LRUHandle* e = lru_.next; + assert(e->refs == 1); + bool erased = FinishErase(table_.Remove(e->key(), e->hash)); + if (!erased) { // to avoid unused variable when compiled NDEBUG + assert(erased); + } + } } static const int kNumShardBits = 4; @@ -314,6 +382,18 @@ class ShardedLRUCache : public Cache { MutexLock l(&id_mutex_); return ++(last_id_); } + virtual void Prune() { + for (int s = 0; s < kNumShards; s++) { + shard_[s].Prune(); + } + } + virtual size_t TotalCharge() const { + size_t total = 0; + for (int s = 0; s < kNumShards; s++) { + total += shard_[s].TotalCharge(); + } + return total; + } }; } // end anonymous namespace diff --git a/src/leveldb/util/cache_test.cc b/src/leveldb/util/cache_test.cc index 43716715a8..468f7a6425 100644 --- a/src/leveldb/util/cache_test.cc +++ b/src/leveldb/util/cache_test.cc @@ -59,6 +59,11 @@ class CacheTest { &CacheTest::Deleter)); } + Cache::Handle* InsertAndReturnHandle(int key, int value, int charge = 1) { + return cache_->Insert(EncodeKey(key), EncodeValue(value), charge, + &CacheTest::Deleter); + } + void Erase(int key) { cache_->Erase(EncodeKey(key)); } @@ -135,8 +140,11 @@ TEST(CacheTest, EntriesArePinned) { TEST(CacheTest, EvictionPolicy) { Insert(100, 101); Insert(200, 201); + Insert(300, 301); + Cache::Handle* h = cache_->Lookup(EncodeKey(300)); - // Frequently used entry must be kept around + // Frequently used entry must be kept around, + // as must things that are still in use. for (int i = 0; i < kCacheSize + 100; i++) { Insert(1000+i, 2000+i); ASSERT_EQ(2000+i, Lookup(1000+i)); @@ -144,6 +152,25 @@ TEST(CacheTest, EvictionPolicy) { } ASSERT_EQ(101, Lookup(100)); ASSERT_EQ(-1, Lookup(200)); + ASSERT_EQ(301, Lookup(300)); + cache_->Release(h); +} + +TEST(CacheTest, UseExceedsCacheSize) { + // Overfill the cache, keeping handles on all inserted entries. + std::vector<Cache::Handle*> h; + for (int i = 0; i < kCacheSize + 100; i++) { + h.push_back(InsertAndReturnHandle(1000+i, 2000+i)); + } + + // Check that all the entries can be found in the cache. + for (int i = 0; i < h.size(); i++) { + ASSERT_EQ(2000+i, Lookup(1000+i)); + } + + for (int i = 0; i < h.size(); i++) { + cache_->Release(h[i]); + } } TEST(CacheTest, HeavyEntries) { @@ -179,6 +206,19 @@ TEST(CacheTest, NewId) { ASSERT_NE(a, b); } +TEST(CacheTest, Prune) { + Insert(1, 100); + Insert(2, 200); + + Cache::Handle* handle = cache_->Lookup(EncodeKey(1)); + ASSERT_TRUE(handle); + cache_->Prune(); + cache_->Release(handle); + + ASSERT_EQ(100, Lookup(1)); + ASSERT_EQ(-1, Lookup(2)); +} + } // namespace leveldb int main(int argc, char** argv) { diff --git a/src/leveldb/util/env.cc b/src/leveldb/util/env.cc index c2600e964a..c58a0821ef 100644 --- a/src/leveldb/util/env.cc +++ b/src/leveldb/util/env.cc @@ -9,6 +9,10 @@ namespace leveldb { Env::~Env() { } +Status Env::NewAppendableFile(const std::string& fname, WritableFile** result) { + return Status::NotSupported("NewAppendableFile", fname); +} + SequentialFile::~SequentialFile() { } diff --git a/src/leveldb/util/env_posix.cc b/src/leveldb/util/env_posix.cc index ba2667864a..e0fca52f46 100644 --- a/src/leveldb/util/env_posix.cc +++ b/src/leveldb/util/env_posix.cc @@ -351,6 +351,19 @@ class PosixEnv : public Env { return s; } + virtual Status NewAppendableFile(const std::string& fname, + WritableFile** result) { + Status s; + FILE* f = fopen(fname.c_str(), "a"); + if (f == NULL) { + *result = NULL; + s = IOError(fname, errno); + } else { + *result = new PosixWritableFile(fname, f); + } + return s; + } + virtual bool FileExists(const std::string& fname) { return access(fname.c_str(), F_OK) == 0; } diff --git a/src/leveldb/util/env_win.cc b/src/leveldb/util/env_win.cc index e11a96b791..b074b7579e 100644 --- a/src/leveldb/util/env_win.cc +++ b/src/leveldb/util/env_win.cc @@ -106,7 +106,7 @@ private: class Win32WritableFile : public WritableFile { public: - Win32WritableFile(const std::string& fname); + Win32WritableFile(const std::string& fname, bool append); ~Win32WritableFile(); virtual Status Append(const Slice& data); @@ -158,6 +158,8 @@ public: RandomAccessFile** result); virtual Status NewWritableFile(const std::string& fname, WritableFile** result); + virtual Status NewAppendableFile(const std::string& fname, + WritableFile** result); virtual bool FileExists(const std::string& fname); @@ -423,17 +425,23 @@ void Win32RandomAccessFile::_CleanUp() } } -Win32WritableFile::Win32WritableFile(const std::string& fname) +Win32WritableFile::Win32WritableFile(const std::string& fname, bool append) : filename_(fname) { std::wstring path; ToWidePath(fname, path); - DWORD Flag = PathFileExistsW(path.c_str()) ? OPEN_EXISTING : CREATE_ALWAYS; + // NewAppendableFile: append to an existing file, or create a new one + // if none exists - this is OPEN_ALWAYS behavior, with + // FILE_APPEND_DATA to avoid having to manually position the file + // pointer at the end of the file. + // NewWritableFile: create a new file, delete if it exists - this is + // CREATE_ALWAYS behavior. This file is used for writing only so + // use GENERIC_WRITE. _hFile = CreateFileW(path.c_str(), - GENERIC_READ | GENERIC_WRITE, + append ? FILE_APPEND_DATA : GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_DELETE|FILE_SHARE_WRITE, NULL, - Flag, + append ? OPEN_ALWAYS : CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL); // CreateFileW returns INVALID_HANDLE_VALUE in case of error, always check isEnable() before use @@ -823,7 +831,9 @@ Status Win32Env::NewLogger( const std::string& fname, Logger** result ) { Status sRet; std::string path = fname; - Win32WritableFile* pMapFile = new Win32WritableFile(ModifyPath(path)); + // Logs are opened with write semantics, not with append semantics + // (see PosixEnv::NewLogger) + Win32WritableFile* pMapFile = new Win32WritableFile(ModifyPath(path), false); if(!pMapFile->isEnable()){ delete pMapFile; *result = NULL; @@ -837,7 +847,20 @@ Status Win32Env::NewWritableFile( const std::string& fname, WritableFile** resul { Status sRet; std::string path = fname; - Win32WritableFile* pFile = new Win32WritableFile(ModifyPath(path)); + Win32WritableFile* pFile = new Win32WritableFile(ModifyPath(path), false); + if(!pFile->isEnable()){ + *result = NULL; + sRet = Status::IOError(fname,Win32::GetLastErrSz()); + }else + *result = pFile; + return sRet; +} + +Status Win32Env::NewAppendableFile( const std::string& fname, WritableFile** result ) +{ + Status sRet; + std::string path = fname; + Win32WritableFile* pFile = new Win32WritableFile(ModifyPath(path), true); if(!pFile->isEnable()){ *result = NULL; sRet = Status::IOError(fname,Win32::GetLastErrSz()); diff --git a/src/leveldb/util/options.cc b/src/leveldb/util/options.cc index 76af5b9302..8b618fb1ae 100644 --- a/src/leveldb/util/options.cc +++ b/src/leveldb/util/options.cc @@ -22,8 +22,8 @@ Options::Options() block_size(4096), block_restart_interval(16), compression(kSnappyCompression), + reuse_logs(false), filter_policy(NULL) { } - } // namespace leveldb diff --git a/src/leveldb/util/testutil.h b/src/leveldb/util/testutil.h index adad3fc1ea..d7e4583702 100644 --- a/src/leveldb/util/testutil.h +++ b/src/leveldb/util/testutil.h @@ -45,6 +45,16 @@ class ErrorEnv : public EnvWrapper { } return target()->NewWritableFile(fname, result); } + + virtual Status NewAppendableFile(const std::string& fname, + WritableFile** result) { + if (writable_file_error_) { + ++num_writable_file_errors_; + *result = NULL; + return Status::IOError(fname, "fake error"); + } + return target()->NewAppendableFile(fname, result); + } }; } // namespace test |