a4a4a2dabd
Summary: Previously, a `ReadOptions` object was stored in every `BlockBasedTableIterator` and every `LevelIterator`. This redundancy consumes extra memory, resulting in the `Arena` making more allocations, and iteration observing worse cache performance. This PR migrates callers of `NewInternalIterator()` and `MakeInputIterator()` to provide a `ReadOptions` object guaranteed to outlive the returned iterator. When the iterator's lifetime will be managed by the user, this lifetime guarantee is achieved by storing the `ReadOptions` value in `ArenaWrappedDBIter`. Then, sub-iterators of `NewInternalIterator()` and `MakeInputIterator()` can hold a reference-to-const `ReadOptions`. Pull Request resolved: https://github.com/facebook/rocksdb/pull/7210 Test Plan: - `make check` under ASAN and valgrind - benchmark: on a DB with 2 L0 files and 3 L1+ levels, this PR reduced `Arena` allocation 4792 -> 4160 bytes. Reviewed By: anand1976 Differential Revision: D22861323 Pulled By: ajkr fbshipit-source-id: 54aebb3e89c872eeab0f5793b4b6e42878d093ce
82 lines
2.7 KiB
C++
82 lines
2.7 KiB
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
|
|
#ifndef ROCKSDB_LITE
|
|
|
|
#include "rocksdb/utilities/debug.h"
|
|
|
|
#include "db/db_impl/db_impl.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
|
|
Status GetAllKeyVersions(DB* db, Slice begin_key, Slice end_key,
|
|
size_t max_num_ikeys,
|
|
std::vector<KeyVersion>* key_versions) {
|
|
if (nullptr == db) {
|
|
return Status::InvalidArgument("db cannot be null.");
|
|
}
|
|
return GetAllKeyVersions(db, db->DefaultColumnFamily(), begin_key, end_key,
|
|
max_num_ikeys, key_versions);
|
|
}
|
|
|
|
Status GetAllKeyVersions(DB* db, ColumnFamilyHandle* cfh, Slice begin_key,
|
|
Slice end_key, size_t max_num_ikeys,
|
|
std::vector<KeyVersion>* key_versions) {
|
|
if (nullptr == db) {
|
|
return Status::InvalidArgument("db cannot be null.");
|
|
}
|
|
if (nullptr == cfh) {
|
|
return Status::InvalidArgument("Column family handle cannot be null.");
|
|
}
|
|
if (nullptr == key_versions) {
|
|
return Status::InvalidArgument("key_versions cannot be null.");
|
|
}
|
|
key_versions->clear();
|
|
|
|
DBImpl* idb = static_cast<DBImpl*>(db->GetRootDB());
|
|
auto icmp = InternalKeyComparator(idb->GetOptions(cfh).comparator);
|
|
ReadOptions read_options;
|
|
ReadRangeDelAggregator range_del_agg(&icmp,
|
|
kMaxSequenceNumber /* upper_bound */);
|
|
Arena arena;
|
|
ScopedArenaIterator iter(idb->NewInternalIterator(
|
|
read_options, &arena, &range_del_agg, kMaxSequenceNumber, cfh));
|
|
|
|
if (!begin_key.empty()) {
|
|
InternalKey ikey;
|
|
ikey.SetMinPossibleForUserKey(begin_key);
|
|
iter->Seek(ikey.Encode());
|
|
} else {
|
|
iter->SeekToFirst();
|
|
}
|
|
|
|
size_t num_keys = 0;
|
|
for (; iter->Valid(); iter->Next()) {
|
|
ParsedInternalKey ikey;
|
|
if (!ParseInternalKey(iter->key(), &ikey)) {
|
|
return Status::Corruption("Internal Key [" + iter->key().ToString() +
|
|
"] parse error!");
|
|
}
|
|
|
|
if (!end_key.empty() &&
|
|
icmp.user_comparator()->Compare(ikey.user_key, end_key) > 0) {
|
|
break;
|
|
}
|
|
|
|
key_versions->emplace_back(ikey.user_key.ToString() /* _user_key */,
|
|
iter->value().ToString() /* _value */,
|
|
ikey.sequence /* _sequence */,
|
|
static_cast<int>(ikey.type) /* _type */);
|
|
if (++num_keys >= max_num_ikeys) {
|
|
break;
|
|
}
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|
|
|
|
#endif // ROCKSDB_LITE
|