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-rw-r--r--src/rocksdb/examples/.gitignore9
-rw-r--r--src/rocksdb/examples/Makefile53
-rw-r--r--src/rocksdb/examples/README.md2
-rw-r--r--src/rocksdb/examples/c_simple_example.c79
-rw-r--r--src/rocksdb/examples/column_families_example.cc72
-rw-r--r--src/rocksdb/examples/compact_files_example.cc171
-rw-r--r--src/rocksdb/examples/compaction_filter_example.cc88
-rw-r--r--src/rocksdb/examples/multi_processes_example.cc395
-rw-r--r--src/rocksdb/examples/optimistic_transaction_example.cc180
-rw-r--r--src/rocksdb/examples/options_file_example.cc113
-rw-r--r--src/rocksdb/examples/rocksdb_option_file_example.ini144
-rw-r--r--src/rocksdb/examples/simple_example.cc83
-rw-r--r--src/rocksdb/examples/transaction_example.cc186
13 files changed, 1575 insertions, 0 deletions
diff --git a/src/rocksdb/examples/.gitignore b/src/rocksdb/examples/.gitignore
new file mode 100644
index 000000000..823664ae1
--- /dev/null
+++ b/src/rocksdb/examples/.gitignore
@@ -0,0 +1,9 @@
+c_simple_example
+column_families_example
+compact_files_example
+compaction_filter_example
+multi_processes_example
+optimistic_transaction_example
+options_file_example
+simple_example
+transaction_example
diff --git a/src/rocksdb/examples/Makefile b/src/rocksdb/examples/Makefile
new file mode 100644
index 000000000..27a6f0f42
--- /dev/null
+++ b/src/rocksdb/examples/Makefile
@@ -0,0 +1,53 @@
+include ../make_config.mk
+
+ifndef DISABLE_JEMALLOC
+ ifdef JEMALLOC
+ PLATFORM_CXXFLAGS += -DROCKSDB_JEMALLOC -DJEMALLOC_NO_DEMANGLE
+ endif
+ EXEC_LDFLAGS := $(JEMALLOC_LIB) $(EXEC_LDFLAGS) -lpthread
+ PLATFORM_CXXFLAGS += $(JEMALLOC_INCLUDE)
+endif
+
+ifneq ($(USE_RTTI), 1)
+ CXXFLAGS += -fno-rtti
+endif
+
+.PHONY: clean librocksdb
+
+all: simple_example column_families_example compact_files_example c_simple_example optimistic_transaction_example transaction_example compaction_filter_example options_file_example
+
+simple_example: librocksdb simple_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+column_families_example: librocksdb column_families_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+compaction_filter_example: librocksdb compaction_filter_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+compact_files_example: librocksdb compact_files_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+.c.o:
+ $(CC) $(CFLAGS) -c $< -o $@ -I../include
+
+c_simple_example: librocksdb c_simple_example.o
+ $(CXX) $@.o -o$@ ../librocksdb.a $(PLATFORM_LDFLAGS) $(EXEC_LDFLAGS)
+
+optimistic_transaction_example: librocksdb optimistic_transaction_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+transaction_example: librocksdb transaction_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+options_file_example: librocksdb options_file_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+multi_processes_example: librocksdb multi_processes_example.cc
+ $(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
+
+clean:
+ rm -rf ./simple_example ./column_families_example ./compact_files_example ./compaction_filter_example ./c_simple_example c_simple_example.o ./optimistic_transaction_example ./transaction_example ./options_file_example ./multi_processes_example
+
+librocksdb:
+ cd .. && $(MAKE) static_lib
diff --git a/src/rocksdb/examples/README.md b/src/rocksdb/examples/README.md
new file mode 100644
index 000000000..f4ba2384b
--- /dev/null
+++ b/src/rocksdb/examples/README.md
@@ -0,0 +1,2 @@
+1. Compile RocksDB first by executing `make static_lib` in parent dir
+2. Compile all examples: `cd examples/; make all`
diff --git a/src/rocksdb/examples/c_simple_example.c b/src/rocksdb/examples/c_simple_example.c
new file mode 100644
index 000000000..5564361d1
--- /dev/null
+++ b/src/rocksdb/examples/c_simple_example.c
@@ -0,0 +1,79 @@
+// 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).
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include "rocksdb/c.h"
+
+#include <unistd.h> // sysconf() - get CPU count
+
+const char DBPath[] = "/tmp/rocksdb_simple_example";
+const char DBBackupPath[] = "/tmp/rocksdb_simple_example_backup";
+
+int main(int argc, char **argv) {
+ rocksdb_t *db;
+ rocksdb_backup_engine_t *be;
+ rocksdb_options_t *options = rocksdb_options_create();
+ // Optimize RocksDB. This is the easiest way to
+ // get RocksDB to perform well
+ long cpus = sysconf(_SC_NPROCESSORS_ONLN); // get # of online cores
+ rocksdb_options_increase_parallelism(options, (int)(cpus));
+ rocksdb_options_optimize_level_style_compaction(options, 0);
+ // create the DB if it's not already present
+ rocksdb_options_set_create_if_missing(options, 1);
+
+ // open DB
+ char *err = NULL;
+ db = rocksdb_open(options, DBPath, &err);
+ assert(!err);
+
+ // open Backup Engine that we will use for backing up our database
+ be = rocksdb_backup_engine_open(options, DBBackupPath, &err);
+ assert(!err);
+
+ // Put key-value
+ rocksdb_writeoptions_t *writeoptions = rocksdb_writeoptions_create();
+ const char key[] = "key";
+ const char *value = "value";
+ rocksdb_put(db, writeoptions, key, strlen(key), value, strlen(value) + 1,
+ &err);
+ assert(!err);
+ // Get value
+ rocksdb_readoptions_t *readoptions = rocksdb_readoptions_create();
+ size_t len;
+ char *returned_value =
+ rocksdb_get(db, readoptions, key, strlen(key), &len, &err);
+ assert(!err);
+ assert(strcmp(returned_value, "value") == 0);
+ free(returned_value);
+
+ // create new backup in a directory specified by DBBackupPath
+ rocksdb_backup_engine_create_new_backup(be, db, &err);
+ assert(!err);
+
+ rocksdb_close(db);
+
+ // If something is wrong, you might want to restore data from last backup
+ rocksdb_restore_options_t *restore_options = rocksdb_restore_options_create();
+ rocksdb_backup_engine_restore_db_from_latest_backup(be, DBPath, DBPath,
+ restore_options, &err);
+ assert(!err);
+ rocksdb_restore_options_destroy(restore_options);
+
+ db = rocksdb_open(options, DBPath, &err);
+ assert(!err);
+
+ // cleanup
+ rocksdb_writeoptions_destroy(writeoptions);
+ rocksdb_readoptions_destroy(readoptions);
+ rocksdb_options_destroy(options);
+ rocksdb_backup_engine_close(be);
+ rocksdb_close(db);
+
+ return 0;
+}
diff --git a/src/rocksdb/examples/column_families_example.cc b/src/rocksdb/examples/column_families_example.cc
new file mode 100644
index 000000000..df936d46a
--- /dev/null
+++ b/src/rocksdb/examples/column_families_example.cc
@@ -0,0 +1,72 @@
+// 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).
+#include <cstdio>
+#include <string>
+#include <vector>
+
+#include "rocksdb/db.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/options.h"
+
+using namespace ROCKSDB_NAMESPACE;
+
+std::string kDBPath = "/tmp/rocksdb_column_families_example";
+
+int main() {
+ // open DB
+ Options options;
+ options.create_if_missing = true;
+ DB* db;
+ Status s = DB::Open(options, kDBPath, &db);
+ assert(s.ok());
+
+ // create column family
+ ColumnFamilyHandle* cf;
+ s = db->CreateColumnFamily(ColumnFamilyOptions(), "new_cf", &cf);
+ assert(s.ok());
+
+ // close DB
+ delete cf;
+ delete db;
+
+ // open DB with two column families
+ std::vector<ColumnFamilyDescriptor> column_families;
+ // have to open default column family
+ column_families.push_back(ColumnFamilyDescriptor(
+ kDefaultColumnFamilyName, ColumnFamilyOptions()));
+ // open the new one, too
+ column_families.push_back(ColumnFamilyDescriptor(
+ "new_cf", ColumnFamilyOptions()));
+ std::vector<ColumnFamilyHandle*> handles;
+ s = DB::Open(DBOptions(), kDBPath, column_families, &handles, &db);
+ assert(s.ok());
+
+ // put and get from non-default column family
+ s = db->Put(WriteOptions(), handles[1], Slice("key"), Slice("value"));
+ assert(s.ok());
+ std::string value;
+ s = db->Get(ReadOptions(), handles[1], Slice("key"), &value);
+ assert(s.ok());
+
+ // atomic write
+ WriteBatch batch;
+ batch.Put(handles[0], Slice("key2"), Slice("value2"));
+ batch.Put(handles[1], Slice("key3"), Slice("value3"));
+ batch.Delete(handles[0], Slice("key"));
+ s = db->Write(WriteOptions(), &batch);
+ assert(s.ok());
+
+ // drop column family
+ s = db->DropColumnFamily(handles[1]);
+ assert(s.ok());
+
+ // close db
+ for (auto handle : handles) {
+ delete handle;
+ }
+ delete db;
+
+ return 0;
+}
diff --git a/src/rocksdb/examples/compact_files_example.cc b/src/rocksdb/examples/compact_files_example.cc
new file mode 100644
index 000000000..a0a9fa90a
--- /dev/null
+++ b/src/rocksdb/examples/compact_files_example.cc
@@ -0,0 +1,171 @@
+// 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).
+//
+// An example code demonstrating how to use CompactFiles, EventListener,
+// and GetColumnFamilyMetaData APIs to implement custom compaction algorithm.
+
+#include <mutex>
+#include <string>
+#include "rocksdb/db.h"
+#include "rocksdb/env.h"
+#include "rocksdb/options.h"
+
+using namespace ROCKSDB_NAMESPACE;
+std::string kDBPath = "/tmp/rocksdb_compact_files_example";
+struct CompactionTask;
+
+// This is an example interface of external-compaction algorithm.
+// Compaction algorithm can be implemented outside the core-RocksDB
+// code by using the pluggable compaction APIs that RocksDb provides.
+class Compactor : public EventListener {
+ public:
+ // Picks and returns a compaction task given the specified DB
+ // and column family. It is the caller's responsibility to
+ // destroy the returned CompactionTask. Returns "nullptr"
+ // if it cannot find a proper compaction task.
+ virtual CompactionTask* PickCompaction(
+ DB* db, const std::string& cf_name) = 0;
+
+ // Schedule and run the specified compaction task in background.
+ virtual void ScheduleCompaction(CompactionTask *task) = 0;
+};
+
+// Example structure that describes a compaction task.
+struct CompactionTask {
+ CompactionTask(
+ DB* _db, Compactor* _compactor,
+ const std::string& _column_family_name,
+ const std::vector<std::string>& _input_file_names,
+ const int _output_level,
+ const CompactionOptions& _compact_options,
+ bool _retry_on_fail)
+ : db(_db),
+ compactor(_compactor),
+ column_family_name(_column_family_name),
+ input_file_names(_input_file_names),
+ output_level(_output_level),
+ compact_options(_compact_options),
+ retry_on_fail(_retry_on_fail) {}
+ DB* db;
+ Compactor* compactor;
+ const std::string& column_family_name;
+ std::vector<std::string> input_file_names;
+ int output_level;
+ CompactionOptions compact_options;
+ bool retry_on_fail;
+};
+
+// A simple compaction algorithm that always compacts everything
+// to the highest level whenever possible.
+class FullCompactor : public Compactor {
+ public:
+ explicit FullCompactor(const Options options) : options_(options) {
+ compact_options_.compression = options_.compression;
+ compact_options_.output_file_size_limit =
+ options_.target_file_size_base;
+ }
+
+ // When flush happens, it determines whether to trigger compaction. If
+ // triggered_writes_stop is true, it will also set the retry flag of
+ // compaction-task to true.
+ void OnFlushCompleted(
+ DB* db, const FlushJobInfo& info) override {
+ CompactionTask* task = PickCompaction(db, info.cf_name);
+ if (task != nullptr) {
+ if (info.triggered_writes_stop) {
+ task->retry_on_fail = true;
+ }
+ // Schedule compaction in a different thread.
+ ScheduleCompaction(task);
+ }
+ }
+
+ // Always pick a compaction which includes all files whenever possible.
+ CompactionTask* PickCompaction(
+ DB* db, const std::string& cf_name) override {
+ ColumnFamilyMetaData cf_meta;
+ db->GetColumnFamilyMetaData(&cf_meta);
+
+ std::vector<std::string> input_file_names;
+ for (auto level : cf_meta.levels) {
+ for (auto file : level.files) {
+ if (file.being_compacted) {
+ return nullptr;
+ }
+ input_file_names.push_back(file.name);
+ }
+ }
+ return new CompactionTask(
+ db, this, cf_name, input_file_names,
+ options_.num_levels - 1, compact_options_, false);
+ }
+
+ // Schedule the specified compaction task in background.
+ void ScheduleCompaction(CompactionTask* task) override {
+ options_.env->Schedule(&FullCompactor::CompactFiles, task);
+ }
+
+ static void CompactFiles(void* arg) {
+ std::unique_ptr<CompactionTask> task(
+ reinterpret_cast<CompactionTask*>(arg));
+ assert(task);
+ assert(task->db);
+ Status s = task->db->CompactFiles(
+ task->compact_options,
+ task->input_file_names,
+ task->output_level);
+ printf("CompactFiles() finished with status %s\n", s.ToString().c_str());
+ if (!s.ok() && !s.IsIOError() && task->retry_on_fail) {
+ // If a compaction task with its retry_on_fail=true failed,
+ // try to schedule another compaction in case the reason
+ // is not an IO error.
+ CompactionTask* new_task = task->compactor->PickCompaction(
+ task->db, task->column_family_name);
+ task->compactor->ScheduleCompaction(new_task);
+ }
+ }
+
+ private:
+ Options options_;
+ CompactionOptions compact_options_;
+};
+
+int main() {
+ Options options;
+ options.create_if_missing = true;
+ // Disable RocksDB background compaction.
+ options.compaction_style = kCompactionStyleNone;
+ // Small slowdown and stop trigger for experimental purpose.
+ options.level0_slowdown_writes_trigger = 3;
+ options.level0_stop_writes_trigger = 5;
+ options.IncreaseParallelism(5);
+ options.listeners.emplace_back(new FullCompactor(options));
+
+ DB* db = nullptr;
+ DestroyDB(kDBPath, options);
+ Status s = DB::Open(options, kDBPath, &db);
+ assert(s.ok());
+ assert(db);
+
+ // if background compaction is not working, write will stall
+ // because of options.level0_stop_writes_trigger
+ for (int i = 1000; i < 99999; ++i) {
+ db->Put(WriteOptions(), std::to_string(i),
+ std::string(500, 'a' + (i % 26)));
+ }
+
+ // verify the values are still there
+ std::string value;
+ for (int i = 1000; i < 99999; ++i) {
+ db->Get(ReadOptions(), std::to_string(i),
+ &value);
+ assert(value == std::string(500, 'a' + (i % 26)));
+ }
+
+ // close the db.
+ delete db;
+
+ return 0;
+}
diff --git a/src/rocksdb/examples/compaction_filter_example.cc b/src/rocksdb/examples/compaction_filter_example.cc
new file mode 100644
index 000000000..cee763195
--- /dev/null
+++ b/src/rocksdb/examples/compaction_filter_example.cc
@@ -0,0 +1,88 @@
+// 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).
+
+#include <rocksdb/compaction_filter.h>
+#include <rocksdb/db.h>
+#include <rocksdb/merge_operator.h>
+#include <rocksdb/options.h>
+
+class MyMerge : public ROCKSDB_NAMESPACE::MergeOperator {
+ public:
+ virtual bool FullMergeV2(const MergeOperationInput& merge_in,
+ MergeOperationOutput* merge_out) const override {
+ merge_out->new_value.clear();
+ if (merge_in.existing_value != nullptr) {
+ merge_out->new_value.assign(merge_in.existing_value->data(),
+ merge_in.existing_value->size());
+ }
+ for (const ROCKSDB_NAMESPACE::Slice& m : merge_in.operand_list) {
+ fprintf(stderr, "Merge(%s)\n", m.ToString().c_str());
+ // the compaction filter filters out bad values
+ assert(m.ToString() != "bad");
+ merge_out->new_value.assign(m.data(), m.size());
+ }
+ return true;
+ }
+
+ const char* Name() const override { return "MyMerge"; }
+};
+
+class MyFilter : public ROCKSDB_NAMESPACE::CompactionFilter {
+ public:
+ bool Filter(int level, const ROCKSDB_NAMESPACE::Slice& key,
+ const ROCKSDB_NAMESPACE::Slice& existing_value,
+ std::string* new_value, bool* value_changed) const override {
+ fprintf(stderr, "Filter(%s)\n", key.ToString().c_str());
+ ++count_;
+ assert(*value_changed == false);
+ return false;
+ }
+
+ bool FilterMergeOperand(
+ int level, const ROCKSDB_NAMESPACE::Slice& key,
+ const ROCKSDB_NAMESPACE::Slice& existing_value) const override {
+ fprintf(stderr, "FilterMerge(%s)\n", key.ToString().c_str());
+ ++merge_count_;
+ return existing_value == "bad";
+ }
+
+ const char* Name() const override { return "MyFilter"; }
+
+ mutable int count_ = 0;
+ mutable int merge_count_ = 0;
+};
+
+int main() {
+ ROCKSDB_NAMESPACE::DB* raw_db;
+ ROCKSDB_NAMESPACE::Status status;
+
+ MyFilter filter;
+
+ int ret = system("rm -rf /tmp/rocksmergetest");
+ if (ret != 0) {
+ fprintf(stderr, "Error deleting /tmp/rocksmergetest, code: %d\n", ret);
+ return ret;
+ }
+ ROCKSDB_NAMESPACE::Options options;
+ options.create_if_missing = true;
+ options.merge_operator.reset(new MyMerge);
+ options.compaction_filter = &filter;
+ status = ROCKSDB_NAMESPACE::DB::Open(options, "/tmp/rocksmergetest", &raw_db);
+ assert(status.ok());
+ std::unique_ptr<ROCKSDB_NAMESPACE::DB> db(raw_db);
+
+ ROCKSDB_NAMESPACE::WriteOptions wopts;
+ db->Merge(wopts, "0", "bad"); // This is filtered out
+ db->Merge(wopts, "1", "data1");
+ db->Merge(wopts, "1", "bad");
+ db->Merge(wopts, "1", "data2");
+ db->Merge(wopts, "1", "bad");
+ db->Merge(wopts, "3", "data3");
+ db->CompactRange(ROCKSDB_NAMESPACE::CompactRangeOptions(), nullptr, nullptr);
+ fprintf(stderr, "filter.count_ = %d\n", filter.count_);
+ assert(filter.count_ == 0);
+ fprintf(stderr, "filter.merge_count_ = %d\n", filter.merge_count_);
+ assert(filter.merge_count_ == 6);
+}
diff --git a/src/rocksdb/examples/multi_processes_example.cc b/src/rocksdb/examples/multi_processes_example.cc
new file mode 100644
index 000000000..3241e36ea
--- /dev/null
+++ b/src/rocksdb/examples/multi_processes_example.cc
@@ -0,0 +1,395 @@
+// 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).
+
+// How to use this example
+// Open two terminals, in one of them, run `./multi_processes_example 0` to
+// start a process running the primary instance. This will create a new DB in
+// kDBPath. The process will run for a while inserting keys to the normal
+// RocksDB database.
+// Next, go to the other terminal and run `./multi_processes_example 1` to
+// start a process running the secondary instance. This will create a secondary
+// instance following the aforementioned primary instance. This process will
+// run for a while, tailing the logs of the primary. After process with primary
+// instance exits, this process will keep running until you hit 'CTRL+C'.
+
+#include <chrono>
+#include <cinttypes>
+#include <cstdio>
+#include <cstdlib>
+#include <ctime>
+#include <string>
+#include <thread>
+#include <vector>
+
+#if defined(OS_LINUX)
+#include <dirent.h>
+#include <signal.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#endif // !OS_LINUX
+
+#include "rocksdb/db.h"
+#include "rocksdb/options.h"
+#include "rocksdb/slice.h"
+
+using ROCKSDB_NAMESPACE::ColumnFamilyDescriptor;
+using ROCKSDB_NAMESPACE::ColumnFamilyHandle;
+using ROCKSDB_NAMESPACE::ColumnFamilyOptions;
+using ROCKSDB_NAMESPACE::DB;
+using ROCKSDB_NAMESPACE::FlushOptions;
+using ROCKSDB_NAMESPACE::Iterator;
+using ROCKSDB_NAMESPACE::Options;
+using ROCKSDB_NAMESPACE::ReadOptions;
+using ROCKSDB_NAMESPACE::Slice;
+using ROCKSDB_NAMESPACE::Status;
+using ROCKSDB_NAMESPACE::WriteOptions;
+
+const std::string kDBPath = "/tmp/rocksdb_multi_processes_example";
+const std::string kPrimaryStatusFile =
+ "/tmp/rocksdb_multi_processes_example_primary_status";
+const uint64_t kMaxKey = 600000;
+const size_t kMaxValueLength = 256;
+const size_t kNumKeysPerFlush = 1000;
+
+const std::vector<std::string>& GetColumnFamilyNames() {
+ static std::vector<std::string> column_family_names = {
+ ROCKSDB_NAMESPACE::kDefaultColumnFamilyName, "pikachu"};
+ return column_family_names;
+}
+
+inline bool IsLittleEndian() {
+ uint32_t x = 1;
+ return *reinterpret_cast<char*>(&x) != 0;
+}
+
+static std::atomic<int>& ShouldSecondaryWait() {
+ static std::atomic<int> should_secondary_wait{1};
+ return should_secondary_wait;
+}
+
+static std::string Key(uint64_t k) {
+ std::string ret;
+ if (IsLittleEndian()) {
+ ret.append(reinterpret_cast<char*>(&k), sizeof(k));
+ } else {
+ char buf[sizeof(k)];
+ buf[0] = k & 0xff;
+ buf[1] = (k >> 8) & 0xff;
+ buf[2] = (k >> 16) & 0xff;
+ buf[3] = (k >> 24) & 0xff;
+ buf[4] = (k >> 32) & 0xff;
+ buf[5] = (k >> 40) & 0xff;
+ buf[6] = (k >> 48) & 0xff;
+ buf[7] = (k >> 56) & 0xff;
+ ret.append(buf, sizeof(k));
+ }
+ size_t i = 0, j = ret.size() - 1;
+ while (i < j) {
+ char tmp = ret[i];
+ ret[i] = ret[j];
+ ret[j] = tmp;
+ ++i;
+ --j;
+ }
+ return ret;
+}
+
+static uint64_t Key(std::string key) {
+ assert(key.size() == sizeof(uint64_t));
+ size_t i = 0, j = key.size() - 1;
+ while (i < j) {
+ char tmp = key[i];
+ key[i] = key[j];
+ key[j] = tmp;
+ ++i;
+ --j;
+ }
+ uint64_t ret = 0;
+ if (IsLittleEndian()) {
+ memcpy(&ret, key.c_str(), sizeof(uint64_t));
+ } else {
+ const char* buf = key.c_str();
+ ret |= static_cast<uint64_t>(buf[0]);
+ ret |= (static_cast<uint64_t>(buf[1]) << 8);
+ ret |= (static_cast<uint64_t>(buf[2]) << 16);
+ ret |= (static_cast<uint64_t>(buf[3]) << 24);
+ ret |= (static_cast<uint64_t>(buf[4]) << 32);
+ ret |= (static_cast<uint64_t>(buf[5]) << 40);
+ ret |= (static_cast<uint64_t>(buf[6]) << 48);
+ ret |= (static_cast<uint64_t>(buf[7]) << 56);
+ }
+ return ret;
+}
+
+static Slice GenerateRandomValue(const size_t max_length, char scratch[]) {
+ size_t sz = 1 + (std::rand() % max_length);
+ int rnd = std::rand();
+ for (size_t i = 0; i != sz; ++i) {
+ scratch[i] = static_cast<char>(rnd ^ i);
+ }
+ return Slice(scratch, sz);
+}
+
+static bool ShouldCloseDB() { return true; }
+
+// TODO: port this example to other systems. It should be straightforward for
+// POSIX-compliant systems.
+#if defined(OS_LINUX)
+void CreateDB() {
+ long my_pid = static_cast<long>(getpid());
+ Options options;
+ Status s = ROCKSDB_NAMESPACE::DestroyDB(kDBPath, options);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to destroy DB: %s\n", my_pid,
+ s.ToString().c_str());
+ assert(false);
+ }
+ options.create_if_missing = true;
+ DB* db = nullptr;
+ s = DB::Open(options, kDBPath, &db);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to open DB: %s\n", my_pid,
+ s.ToString().c_str());
+ assert(false);
+ }
+ std::vector<ColumnFamilyHandle*> handles;
+ ColumnFamilyOptions cf_opts(options);
+ for (const auto& cf_name : GetColumnFamilyNames()) {
+ if (ROCKSDB_NAMESPACE::kDefaultColumnFamilyName != cf_name) {
+ ColumnFamilyHandle* handle = nullptr;
+ s = db->CreateColumnFamily(cf_opts, cf_name, &handle);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to create CF %s: %s\n", my_pid,
+ cf_name.c_str(), s.ToString().c_str());
+ assert(false);
+ }
+ handles.push_back(handle);
+ }
+ }
+ fprintf(stdout, "[process %ld] Column families created\n", my_pid);
+ for (auto h : handles) {
+ delete h;
+ }
+ handles.clear();
+ delete db;
+}
+
+void RunPrimary() {
+ long my_pid = static_cast<long>(getpid());
+ fprintf(stdout, "[process %ld] Primary instance starts\n", my_pid);
+ CreateDB();
+ std::srand(time(nullptr));
+ DB* db = nullptr;
+ Options options;
+ options.create_if_missing = false;
+ std::vector<ColumnFamilyDescriptor> column_families;
+ for (const auto& cf_name : GetColumnFamilyNames()) {
+ column_families.push_back(ColumnFamilyDescriptor(cf_name, options));
+ }
+ std::vector<ColumnFamilyHandle*> handles;
+ WriteOptions write_opts;
+ char val_buf[kMaxValueLength] = {0};
+ uint64_t curr_key = 0;
+ while (curr_key < kMaxKey) {
+ Status s;
+ if (nullptr == db) {
+ s = DB::Open(options, kDBPath, column_families, &handles, &db);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to open DB: %s\n", my_pid,
+ s.ToString().c_str());
+ assert(false);
+ }
+ }
+ assert(nullptr != db);
+ assert(handles.size() == GetColumnFamilyNames().size());
+ for (auto h : handles) {
+ assert(nullptr != h);
+ for (size_t i = 0; i != kNumKeysPerFlush; ++i) {
+ Slice key = Key(curr_key + static_cast<uint64_t>(i));
+ Slice value = GenerateRandomValue(kMaxValueLength, val_buf);
+ s = db->Put(write_opts, h, key, value);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to insert\n", my_pid);
+ assert(false);
+ }
+ }
+ s = db->Flush(FlushOptions(), h);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to flush\n", my_pid);
+ assert(false);
+ }
+ }
+ curr_key += static_cast<uint64_t>(kNumKeysPerFlush);
+ if (ShouldCloseDB()) {
+ for (auto h : handles) {
+ delete h;
+ }
+ handles.clear();
+ delete db;
+ db = nullptr;
+ }
+ }
+ if (nullptr != db) {
+ for (auto h : handles) {
+ delete h;
+ }
+ handles.clear();
+ delete db;
+ db = nullptr;
+ }
+ fprintf(stdout, "[process %ld] Finished adding keys\n", my_pid);
+}
+
+void secondary_instance_sigint_handler(int signal) {
+ ShouldSecondaryWait().store(0, std::memory_order_relaxed);
+ fprintf(stdout, "\n");
+ fflush(stdout);
+};
+
+void RunSecondary() {
+ ::signal(SIGINT, secondary_instance_sigint_handler);
+ long my_pid = static_cast<long>(getpid());
+ const std::string kSecondaryPath =
+ "/tmp/rocksdb_multi_processes_example_secondary";
+ // Create directory if necessary
+ if (nullptr == opendir(kSecondaryPath.c_str())) {
+ int ret =
+ mkdir(kSecondaryPath.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
+ if (ret < 0) {
+ perror("failed to create directory for secondary instance");
+ exit(0);
+ }
+ }
+ DB* db = nullptr;
+ Options options;
+ options.create_if_missing = false;
+ options.max_open_files = -1;
+ Status s = DB::OpenAsSecondary(options, kDBPath, kSecondaryPath, &db);
+ if (!s.ok()) {
+ fprintf(stderr, "[process %ld] Failed to open in secondary mode: %s\n",
+ my_pid, s.ToString().c_str());
+ assert(false);
+ } else {
+ fprintf(stdout, "[process %ld] Secondary instance starts\n", my_pid);
+ }
+
+ ReadOptions ropts;
+ ropts.verify_checksums = true;
+ ropts.total_order_seek = true;
+
+ std::vector<std::thread> test_threads;
+ test_threads.emplace_back([&]() {
+ while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
+ std::unique_ptr<Iterator> iter(db->NewIterator(ropts));
+ iter->SeekToFirst();
+ size_t count = 0;
+ for (; iter->Valid(); iter->Next()) {
+ ++count;
+ }
+ }
+ fprintf(stdout, "[process %ld] Range_scan thread finished\n", my_pid);
+ });
+
+ test_threads.emplace_back([&]() {
+ std::srand(time(nullptr));
+ while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
+ Slice key = Key(std::rand() % kMaxKey);
+ std::string value;
+ db->Get(ropts, key, &value);
+ }
+ fprintf(stdout, "[process %ld] Point lookup thread finished\n");
+ });
+
+ uint64_t curr_key = 0;
+ while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
+ s = db->TryCatchUpWithPrimary();
+ if (!s.ok()) {
+ fprintf(stderr,
+ "[process %ld] error while trying to catch up with "
+ "primary %s\n",
+ my_pid, s.ToString().c_str());
+ assert(false);
+ }
+ {
+ std::unique_ptr<Iterator> iter(db->NewIterator(ropts));
+ if (!iter) {
+ fprintf(stderr, "[process %ld] Failed to create iterator\n", my_pid);
+ assert(false);
+ }
+ iter->SeekToLast();
+ if (iter->Valid()) {
+ uint64_t curr_max_key = Key(iter->key().ToString());
+ if (curr_max_key != curr_key) {
+ fprintf(stdout, "[process %ld] Observed key %" PRIu64 "\n", my_pid,
+ curr_key);
+ curr_key = curr_max_key;
+ }
+ }
+ }
+ std::this_thread::sleep_for(std::chrono::seconds(1));
+ }
+ s = db->TryCatchUpWithPrimary();
+ if (!s.ok()) {
+ fprintf(stderr,
+ "[process %ld] error while trying to catch up with "
+ "primary %s\n",
+ my_pid, s.ToString().c_str());
+ assert(false);
+ }
+
+ std::vector<ColumnFamilyDescriptor> column_families;
+ for (const auto& cf_name : GetColumnFamilyNames()) {
+ column_families.push_back(ColumnFamilyDescriptor(cf_name, options));
+ }
+ std::vector<ColumnFamilyHandle*> handles;
+ DB* verification_db = nullptr;
+ s = DB::OpenForReadOnly(options, kDBPath, column_families, &handles,
+ &verification_db);
+ assert(s.ok());
+ Iterator* iter1 = verification_db->NewIterator(ropts);
+ iter1->SeekToFirst();
+
+ Iterator* iter = db->NewIterator(ropts);
+ iter->SeekToFirst();
+ for (; iter->Valid() && iter1->Valid(); iter->Next(), iter1->Next()) {
+ if (iter->key().ToString() != iter1->key().ToString()) {
+ fprintf(stderr, "%" PRIu64 "!= %" PRIu64 "\n",
+ Key(iter->key().ToString()), Key(iter1->key().ToString()));
+ assert(false);
+ } else if (iter->value().ToString() != iter1->value().ToString()) {
+ fprintf(stderr, "Value mismatch\n");
+ assert(false);
+ }
+ }
+ fprintf(stdout, "[process %ld] Verification succeeded\n", my_pid);
+ for (auto& thr : test_threads) {
+ thr.join();
+ }
+ delete iter;
+ delete iter1;
+ delete db;
+ delete verification_db;
+}
+
+int main(int argc, char** argv) {
+ if (argc < 2) {
+ fprintf(stderr, "%s <0 for primary, 1 for secondary>\n", argv[0]);
+ return 0;
+ }
+ if (atoi(argv[1]) == 0) {
+ RunPrimary();
+ } else {
+ RunSecondary();
+ }
+ return 0;
+}
+#else // OS_LINUX
+int main() {
+ fpritnf(stderr, "Not implemented.\n");
+ return 0;
+}
+#endif // !OS_LINUX
diff --git a/src/rocksdb/examples/optimistic_transaction_example.cc b/src/rocksdb/examples/optimistic_transaction_example.cc
new file mode 100644
index 000000000..fd6dbad63
--- /dev/null
+++ b/src/rocksdb/examples/optimistic_transaction_example.cc
@@ -0,0 +1,180 @@
+// 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/db.h"
+#include "rocksdb/options.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/utilities/transaction.h"
+#include "rocksdb/utilities/optimistic_transaction_db.h"
+
+using namespace ROCKSDB_NAMESPACE;
+
+std::string kDBPath = "/tmp/rocksdb_transaction_example";
+
+int main() {
+ // open DB
+ Options options;
+ options.create_if_missing = true;
+ DB* db;
+ OptimisticTransactionDB* txn_db;
+
+ Status s = OptimisticTransactionDB::Open(options, kDBPath, &txn_db);
+ assert(s.ok());
+ db = txn_db->GetBaseDB();
+
+ WriteOptions write_options;
+ ReadOptions read_options;
+ OptimisticTransactionOptions txn_options;
+ std::string value;
+
+ ////////////////////////////////////////////////////////
+ //
+ // Simple OptimisticTransaction Example ("Read Committed")
+ //
+ ////////////////////////////////////////////////////////
+
+ // Start a transaction
+ Transaction* txn = txn_db->BeginTransaction(write_options);
+ assert(txn);
+
+ // Read a key in this transaction
+ s = txn->Get(read_options, "abc", &value);
+ assert(s.IsNotFound());
+
+ // Write a key in this transaction
+ s = txn->Put("abc", "xyz");
+ assert(s.ok());
+
+ // Read a key OUTSIDE this transaction. Does not affect txn.
+ s = db->Get(read_options, "abc", &value);
+ assert(s.IsNotFound());
+
+ // Write a key OUTSIDE of this transaction.
+ // Does not affect txn since this is an unrelated key. If we wrote key 'abc'
+ // here, the transaction would fail to commit.
+ s = db->Put(write_options, "xyz", "zzz");
+ assert(s.ok());
+ s = db->Put(write_options, "abc", "def");
+ assert(s.ok());
+
+ // Commit transaction
+ s = txn->Commit();
+ assert(s.IsBusy());
+ delete txn;
+
+ s = db->Get(read_options, "xyz", &value);
+ assert(s.ok());
+ assert(value == "zzz");
+
+ s = db->Get(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "def");
+
+ ////////////////////////////////////////////////////////
+ //
+ // "Repeatable Read" (Snapshot Isolation) Example
+ // -- Using a single Snapshot
+ //
+ ////////////////////////////////////////////////////////
+
+ // Set a snapshot at start of transaction by setting set_snapshot=true
+ txn_options.set_snapshot = true;
+ txn = txn_db->BeginTransaction(write_options, txn_options);
+
+ const Snapshot* snapshot = txn->GetSnapshot();
+
+ // Write a key OUTSIDE of transaction
+ s = db->Put(write_options, "abc", "xyz");
+ assert(s.ok());
+
+ // Read a key using the snapshot
+ read_options.snapshot = snapshot;
+ s = txn->GetForUpdate(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "def");
+
+ // Attempt to commit transaction
+ s = txn->Commit();
+
+ // Transaction could not commit since the write outside of the txn conflicted
+ // with the read!
+ assert(s.IsBusy());
+
+ delete txn;
+ // Clear snapshot from read options since it is no longer valid
+ read_options.snapshot = nullptr;
+ snapshot = nullptr;
+
+ s = db->Get(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "xyz");
+
+ ////////////////////////////////////////////////////////
+ //
+ // "Read Committed" (Monotonic Atomic Views) Example
+ // --Using multiple Snapshots
+ //
+ ////////////////////////////////////////////////////////
+
+ // In this example, we set the snapshot multiple times. This is probably
+ // only necessary if you have very strict isolation requirements to
+ // implement.
+
+ // Set a snapshot at start of transaction
+ txn_options.set_snapshot = true;
+ txn = txn_db->BeginTransaction(write_options, txn_options);
+
+ // Do some reads and writes to key "x"
+ read_options.snapshot = db->GetSnapshot();
+ s = txn->Get(read_options, "x", &value);
+ assert(s.IsNotFound());
+ s = txn->Put("x", "x");
+ assert(s.ok());
+
+ // The transaction hasn't committed, so the write is not visible
+ // outside of txn.
+ s = db->Get(read_options, "x", &value);
+ assert(s.IsNotFound());
+
+ // Do a write outside of the transaction to key "y"
+ s = db->Put(write_options, "y", "z");
+ assert(s.ok());
+
+ // Set a new snapshot in the transaction
+ txn->SetSnapshot();
+ read_options.snapshot = db->GetSnapshot();
+
+ // Do some reads and writes to key "y"
+ s = txn->GetForUpdate(read_options, "y", &value);
+ assert(s.ok());
+ assert(value == "z");
+ txn->Put("y", "y");
+
+ // Commit. Since the snapshot was advanced, the write done outside of the
+ // transaction does not prevent this transaction from Committing.
+ s = txn->Commit();
+ assert(s.ok());
+ delete txn;
+ // Clear snapshot from read options since it is no longer valid
+ read_options.snapshot = nullptr;
+
+ // txn is committed, read the latest values.
+ s = db->Get(read_options, "x", &value);
+ assert(s.ok());
+ assert(value == "x");
+
+ s = db->Get(read_options, "y", &value);
+ assert(s.ok());
+ assert(value == "y");
+
+ // Cleanup
+ delete txn_db;
+ DestroyDB(kDBPath, options);
+ return 0;
+}
+
+#endif // ROCKSDB_LITE
diff --git a/src/rocksdb/examples/options_file_example.cc b/src/rocksdb/examples/options_file_example.cc
new file mode 100644
index 000000000..e6a1d0e9a
--- /dev/null
+++ b/src/rocksdb/examples/options_file_example.cc
@@ -0,0 +1,113 @@
+// 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).
+//
+// This file demonstrates how to use the utility functions defined in
+// rocksdb/utilities/options_util.h to open a rocksdb database without
+// remembering all the rocksdb options.
+#include <cstdio>
+#include <string>
+#include <vector>
+
+#include "rocksdb/cache.h"
+#include "rocksdb/compaction_filter.h"
+#include "rocksdb/db.h"
+#include "rocksdb/options.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/table.h"
+#include "rocksdb/utilities/options_util.h"
+
+using namespace ROCKSDB_NAMESPACE;
+
+std::string kDBPath = "/tmp/rocksdb_options_file_example";
+
+namespace {
+// A dummy compaction filter
+class DummyCompactionFilter : public CompactionFilter {
+ public:
+ virtual ~DummyCompactionFilter() {}
+ virtual bool Filter(int level, const Slice& key, const Slice& existing_value,
+ std::string* new_value, bool* value_changed) const {
+ return false;
+ }
+ virtual const char* Name() const { return "DummyCompactionFilter"; }
+};
+
+} // namespace
+
+int main() {
+ DBOptions db_opt;
+ db_opt.create_if_missing = true;
+
+ std::vector<ColumnFamilyDescriptor> cf_descs;
+ cf_descs.push_back({kDefaultColumnFamilyName, ColumnFamilyOptions()});
+ cf_descs.push_back({"new_cf", ColumnFamilyOptions()});
+
+ // initialize BlockBasedTableOptions
+ auto cache = NewLRUCache(1 * 1024 * 1024 * 1024);
+ BlockBasedTableOptions bbt_opts;
+ bbt_opts.block_size = 32 * 1024;
+ bbt_opts.block_cache = cache;
+
+ // initialize column families options
+ std::unique_ptr<CompactionFilter> compaction_filter;
+ compaction_filter.reset(new DummyCompactionFilter());
+ cf_descs[0].options.table_factory.reset(NewBlockBasedTableFactory(bbt_opts));
+ cf_descs[0].options.compaction_filter = compaction_filter.get();
+ cf_descs[1].options.table_factory.reset(NewBlockBasedTableFactory(bbt_opts));
+
+ // destroy and open DB
+ DB* db;
+ Status s = DestroyDB(kDBPath, Options(db_opt, cf_descs[0].options));
+ assert(s.ok());
+ s = DB::Open(Options(db_opt, cf_descs[0].options), kDBPath, &db);
+ assert(s.ok());
+
+ // Create column family, and rocksdb will persist the options.
+ ColumnFamilyHandle* cf;
+ s = db->CreateColumnFamily(ColumnFamilyOptions(), "new_cf", &cf);
+ assert(s.ok());
+
+ // close DB
+ delete cf;
+ delete db;
+
+ // In the following code, we will reopen the rocksdb instance using
+ // the options file stored in the db directory.
+
+ // Load the options file.
+ DBOptions loaded_db_opt;
+ std::vector<ColumnFamilyDescriptor> loaded_cf_descs;
+ s = LoadLatestOptions(kDBPath, Env::Default(), &loaded_db_opt,
+ &loaded_cf_descs);
+ assert(s.ok());
+ assert(loaded_db_opt.create_if_missing == db_opt.create_if_missing);
+
+ // Initialize pointer options for each column family
+ for (size_t i = 0; i < loaded_cf_descs.size(); ++i) {
+ auto* loaded_bbt_opt = reinterpret_cast<BlockBasedTableOptions*>(
+ loaded_cf_descs[0].options.table_factory->GetOptions());
+ // Expect the same as BlockBasedTableOptions will be loaded form file.
+ assert(loaded_bbt_opt->block_size == bbt_opts.block_size);
+ // However, block_cache needs to be manually initialized as documented
+ // in rocksdb/utilities/options_util.h.
+ loaded_bbt_opt->block_cache = cache;
+ }
+ // In addition, as pointer options are initialized with default value,
+ // we need to properly initialized all the pointer options if non-defalut
+ // values are used before calling DB::Open().
+ assert(loaded_cf_descs[0].options.compaction_filter == nullptr);
+ loaded_cf_descs[0].options.compaction_filter = compaction_filter.get();
+
+ // reopen the db using the loaded options.
+ std::vector<ColumnFamilyHandle*> handles;
+ s = DB::Open(loaded_db_opt, kDBPath, loaded_cf_descs, &handles, &db);
+ assert(s.ok());
+
+ // close DB
+ for (auto* handle : handles) {
+ delete handle;
+ }
+ delete db;
+}
diff --git a/src/rocksdb/examples/rocksdb_option_file_example.ini b/src/rocksdb/examples/rocksdb_option_file_example.ini
new file mode 100644
index 000000000..dcbc9a308
--- /dev/null
+++ b/src/rocksdb/examples/rocksdb_option_file_example.ini
@@ -0,0 +1,144 @@
+# This is a RocksDB option file.
+#
+# A typical RocksDB options file has four sections, which are
+# Version section, DBOptions section, at least one CFOptions
+# section, and one TableOptions section for each column family.
+# The RocksDB options file in general follows the basic INI
+# file format with the following extensions / modifications:
+#
+# * Escaped characters
+# We escaped the following characters:
+# - \n -- line feed - new line
+# - \r -- carriage return
+# - \\ -- backslash \
+# - \: -- colon symbol :
+# - \# -- hash tag #
+# * Comments
+# We support # style comments. Comments can appear at the ending
+# part of a line.
+# * Statements
+# A statement is of the form option_name = value.
+# Each statement contains a '=', where extra white-spaces
+# are supported. However, we don't support multi-lined statement.
+# Furthermore, each line can only contain at most one statement.
+# * Sections
+# Sections are of the form [SecitonTitle "SectionArgument"],
+# where section argument is optional.
+# * List
+# We use colon-separated string to represent a list.
+# For instance, n1:n2:n3:n4 is a list containing four values.
+#
+# Below is an example of a RocksDB options file:
+[Version]
+ rocksdb_version=4.3.0
+ options_file_version=1.1
+
+[DBOptions]
+ stats_dump_period_sec=600
+ max_manifest_file_size=18446744073709551615
+ bytes_per_sync=8388608
+ delayed_write_rate=2097152
+ WAL_ttl_seconds=0
+ WAL_size_limit_MB=0
+ max_subcompactions=1
+ wal_dir=
+ wal_bytes_per_sync=0
+ db_write_buffer_size=0
+ keep_log_file_num=1000
+ table_cache_numshardbits=4
+ max_file_opening_threads=1
+ writable_file_max_buffer_size=1048576
+ random_access_max_buffer_size=1048576
+ use_fsync=false
+ max_total_wal_size=0
+ max_open_files=-1
+ skip_stats_update_on_db_open=false
+ max_background_compactions=16
+ manifest_preallocation_size=4194304
+ max_background_flushes=7
+ is_fd_close_on_exec=true
+ max_log_file_size=0
+ advise_random_on_open=true
+ create_missing_column_families=false
+ paranoid_checks=true
+ delete_obsolete_files_period_micros=21600000000
+ log_file_time_to_roll=0
+ compaction_readahead_size=0
+ create_if_missing=false
+ use_adaptive_mutex=false
+ enable_thread_tracking=false
+ allow_fallocate=true
+ error_if_exists=false
+ recycle_log_file_num=0
+ skip_log_error_on_recovery=false
+ db_log_dir=
+ new_table_reader_for_compaction_inputs=true
+ allow_mmap_reads=false
+ allow_mmap_writes=false
+ use_direct_reads=false
+ use_direct_writes=false
+
+
+[CFOptions "default"]
+ compaction_style=kCompactionStyleLevel
+ compaction_filter=nullptr
+ num_levels=6
+ table_factory=BlockBasedTable
+ comparator=leveldb.BytewiseComparator
+ max_sequential_skip_in_iterations=8
+ soft_rate_limit=0.000000
+ max_bytes_for_level_base=1073741824
+ memtable_prefix_bloom_probes=6
+ memtable_prefix_bloom_bits=0
+ memtable_prefix_bloom_huge_page_tlb_size=0
+ max_successive_merges=0
+ arena_block_size=16777216
+ min_write_buffer_number_to_merge=1
+ target_file_size_multiplier=1
+ source_compaction_factor=1
+ max_bytes_for_level_multiplier=8
+ max_bytes_for_level_multiplier_additional=2:3:5
+ compaction_filter_factory=nullptr
+ max_write_buffer_number=8
+ level0_stop_writes_trigger=20
+ compression=kSnappyCompression
+ level0_file_num_compaction_trigger=4
+ purge_redundant_kvs_while_flush=true
+ max_write_buffer_size_to_maintain=0
+ memtable_factory=SkipListFactory
+ max_grandparent_overlap_factor=8
+ expanded_compaction_factor=25
+ hard_pending_compaction_bytes_limit=137438953472
+ inplace_update_num_locks=10000
+ level_compaction_dynamic_level_bytes=true
+ level0_slowdown_writes_trigger=12
+ filter_deletes=false
+ verify_checksums_in_compaction=true
+ min_partial_merge_operands=2
+ paranoid_file_checks=false
+ target_file_size_base=134217728
+ optimize_filters_for_hits=false
+ merge_operator=PutOperator
+ compression_per_level=kNoCompression:kNoCompression:kNoCompression:kSnappyCompression:kSnappyCompression:kSnappyCompression
+ compaction_measure_io_stats=false
+ prefix_extractor=nullptr
+ bloom_locality=0
+ write_buffer_size=134217728
+ disable_auto_compactions=false
+ inplace_update_support=false
+
+[TableOptions/BlockBasedTable "default"]
+ format_version=2
+ whole_key_filtering=true
+ no_block_cache=false
+ checksum=kCRC32c
+ filter_policy=rocksdb.BuiltinBloomFilter
+ block_size_deviation=10
+ block_size=8192
+ block_restart_interval=16
+ cache_index_and_filter_blocks=false
+ pin_l0_filter_and_index_blocks_in_cache=false
+ pin_top_level_index_and_filter=false
+ index_type=kBinarySearch
+ hash_index_allow_collision=true
+ flush_block_policy_factory=FlushBlockBySizePolicyFactory
diff --git a/src/rocksdb/examples/simple_example.cc b/src/rocksdb/examples/simple_example.cc
new file mode 100644
index 000000000..256c965d7
--- /dev/null
+++ b/src/rocksdb/examples/simple_example.cc
@@ -0,0 +1,83 @@
+// 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).
+
+#include <cstdio>
+#include <string>
+
+#include "rocksdb/db.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/options.h"
+
+using namespace ROCKSDB_NAMESPACE;
+
+std::string kDBPath = "/tmp/rocksdb_simple_example";
+
+int main() {
+ DB* db;
+ Options options;
+ // Optimize RocksDB. This is the easiest way to get RocksDB to perform well
+ options.IncreaseParallelism();
+ options.OptimizeLevelStyleCompaction();
+ // create the DB if it's not already present
+ options.create_if_missing = true;
+
+ // open DB
+ Status s = DB::Open(options, kDBPath, &db);
+ assert(s.ok());
+
+ // Put key-value
+ s = db->Put(WriteOptions(), "key1", "value");
+ assert(s.ok());
+ std::string value;
+ // get value
+ s = db->Get(ReadOptions(), "key1", &value);
+ assert(s.ok());
+ assert(value == "value");
+
+ // atomically apply a set of updates
+ {
+ WriteBatch batch;
+ batch.Delete("key1");
+ batch.Put("key2", value);
+ s = db->Write(WriteOptions(), &batch);
+ }
+
+ s = db->Get(ReadOptions(), "key1", &value);
+ assert(s.IsNotFound());
+
+ db->Get(ReadOptions(), "key2", &value);
+ assert(value == "value");
+
+ {
+ PinnableSlice pinnable_val;
+ db->Get(ReadOptions(), db->DefaultColumnFamily(), "key2", &pinnable_val);
+ assert(pinnable_val == "value");
+ }
+
+ {
+ std::string string_val;
+ // If it cannot pin the value, it copies the value to its internal buffer.
+ // The intenral buffer could be set during construction.
+ PinnableSlice pinnable_val(&string_val);
+ db->Get(ReadOptions(), db->DefaultColumnFamily(), "key2", &pinnable_val);
+ assert(pinnable_val == "value");
+ // If the value is not pinned, the internal buffer must have the value.
+ assert(pinnable_val.IsPinned() || string_val == "value");
+ }
+
+ PinnableSlice pinnable_val;
+ db->Get(ReadOptions(), db->DefaultColumnFamily(), "key1", &pinnable_val);
+ assert(s.IsNotFound());
+ // Reset PinnableSlice after each use and before each reuse
+ pinnable_val.Reset();
+ db->Get(ReadOptions(), db->DefaultColumnFamily(), "key2", &pinnable_val);
+ assert(pinnable_val == "value");
+ pinnable_val.Reset();
+ // The Slice pointed by pinnable_val is not valid after this point
+
+ delete db;
+
+ return 0;
+}
diff --git a/src/rocksdb/examples/transaction_example.cc b/src/rocksdb/examples/transaction_example.cc
new file mode 100644
index 000000000..41b233544
--- /dev/null
+++ b/src/rocksdb/examples/transaction_example.cc
@@ -0,0 +1,186 @@
+// 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/db.h"
+#include "rocksdb/options.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/utilities/transaction.h"
+#include "rocksdb/utilities/transaction_db.h"
+
+using namespace ROCKSDB_NAMESPACE;
+
+std::string kDBPath = "/tmp/rocksdb_transaction_example";
+
+int main() {
+ // open DB
+ Options options;
+ TransactionDBOptions txn_db_options;
+ options.create_if_missing = true;
+ TransactionDB* txn_db;
+
+ Status s = TransactionDB::Open(options, txn_db_options, kDBPath, &txn_db);
+ assert(s.ok());
+
+ WriteOptions write_options;
+ ReadOptions read_options;
+ TransactionOptions txn_options;
+ std::string value;
+
+ ////////////////////////////////////////////////////////
+ //
+ // Simple Transaction Example ("Read Committed")
+ //
+ ////////////////////////////////////////////////////////
+
+ // Start a transaction
+ Transaction* txn = txn_db->BeginTransaction(write_options);
+ assert(txn);
+
+ // Read a key in this transaction
+ s = txn->Get(read_options, "abc", &value);
+ assert(s.IsNotFound());
+
+ // Write a key in this transaction
+ s = txn->Put("abc", "def");
+ assert(s.ok());
+
+ // Read a key OUTSIDE this transaction. Does not affect txn.
+ s = txn_db->Get(read_options, "abc", &value);
+ assert(s.IsNotFound());
+
+ // Write a key OUTSIDE of this transaction.
+ // Does not affect txn since this is an unrelated key.
+ s = txn_db->Put(write_options, "xyz", "zzz");
+ assert(s.ok());
+
+ // Write a key OUTSIDE of this transaction.
+ // Fail because the key conflicts with the key written in txn.
+ s = txn_db->Put(write_options, "abc", "def");
+ assert(s.subcode() == Status::kLockTimeout);
+
+ // Value for key "xyz" has been committed, can be read in txn.
+ s = txn->Get(read_options, "xyz", &value);
+ assert(s.ok());
+ assert(value == "zzz");
+
+ // Commit transaction
+ s = txn->Commit();
+ assert(s.ok());
+ delete txn;
+
+ // Value is committed, can be read now.
+ s = txn_db->Get(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "def");
+
+ ////////////////////////////////////////////////////////
+ //
+ // "Repeatable Read" (Snapshot Isolation) Example
+ // -- Using a single Snapshot
+ //
+ ////////////////////////////////////////////////////////
+
+ // Set a snapshot at start of transaction by setting set_snapshot=true
+ txn_options.set_snapshot = true;
+ txn = txn_db->BeginTransaction(write_options, txn_options);
+
+ const Snapshot* snapshot = txn->GetSnapshot();
+
+ // Write a key OUTSIDE of transaction
+ s = txn_db->Put(write_options, "abc", "xyz");
+ assert(s.ok());
+
+ // Read the latest committed value.
+ s = txn->Get(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "xyz");
+
+ // Read the snapshotted value.
+ read_options.snapshot = snapshot;
+ s = txn->Get(read_options, "abc", &value);
+ assert(s.ok());
+ assert(value == "def");
+
+ // Attempt to read a key using the snapshot. This will fail since
+ // the previous write outside this txn conflicts with this read.
+ s = txn->GetForUpdate(read_options, "abc", &value);
+ assert(s.IsBusy());
+
+ txn->Rollback();
+
+ // Snapshot will be released upon deleting the transaction.
+ delete txn;
+ // Clear snapshot from read options since it is no longer valid
+ read_options.snapshot = nullptr;
+ snapshot = nullptr;
+
+ ////////////////////////////////////////////////////////
+ //
+ // "Read Committed" (Monotonic Atomic Views) Example
+ // --Using multiple Snapshots
+ //
+ ////////////////////////////////////////////////////////
+
+ // In this example, we set the snapshot multiple times. This is probably
+ // only necessary if you have very strict isolation requirements to
+ // implement.
+
+ // Set a snapshot at start of transaction
+ txn_options.set_snapshot = true;
+ txn = txn_db->BeginTransaction(write_options, txn_options);
+
+ // Do some reads and writes to key "x"
+ read_options.snapshot = txn_db->GetSnapshot();
+ s = txn->Get(read_options, "x", &value);
+ assert(s.IsNotFound());
+ s = txn->Put("x", "x");
+ assert(s.ok());
+
+ // Do a write outside of the transaction to key "y"
+ s = txn_db->Put(write_options, "y", "y1");
+ assert(s.ok());
+
+ // Set a new snapshot in the transaction
+ txn->SetSnapshot();
+ txn->SetSavePoint();
+ read_options.snapshot = txn_db->GetSnapshot();
+
+ // Do some reads and writes to key "y"
+ // Since the snapshot was advanced, the write done outside of the
+ // transaction does not conflict.
+ s = txn->GetForUpdate(read_options, "y", &value);
+ assert(s.ok());
+ assert(value == "y1");
+ s = txn->Put("y", "y2");
+ assert(s.ok());
+
+ // Decide we want to revert the last write from this transaction.
+ txn->RollbackToSavePoint();
+
+ // Commit.
+ s = txn->Commit();
+ assert(s.ok());
+ delete txn;
+ // Clear snapshot from read options since it is no longer valid
+ read_options.snapshot = nullptr;
+
+ // db state is at the save point.
+ s = txn_db->Get(read_options, "x", &value);
+ assert(s.ok());
+ assert(value == "x");
+
+ s = txn_db->Get(read_options, "y", &value);
+ assert(s.ok());
+ assert(value == "y1");
+
+ // Cleanup
+ delete txn_db;
+ DestroyDB(kDBPath, options);
+ return 0;
+}
+
+#endif // ROCKSDB_LITE
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