#include "leveldb/db.h" #include "leveldb/filter_policy.h" #include "leveldb/env.h" #include "leveldb/db.h" using namespace leveldb; constexpr int value_size = 2048; constexpr int data_size = 128 << 20; #include #include #include using namespace leveldb; // 3. 数据管理(Manifest/创建/恢复数据库) Status OpenDB(std::string dbName, DB **db) { Options options; options.create_if_missing = true; options.filter_policy = NewBloomFilterPolicy(10); return DB::Open(options, dbName, db); } // 1. 存储(数据结构与写入) // 4. 数据合并(Compaction) //void InsertData(DB *db) { // WriteOptions writeOptions; // int key_num = data_size / value_size; // srand(static_cast(time(0))); // // for (int i = 0; i < key_num; i++) { // int key_ = rand() % key_num+1; // std::string key = std::to_string(key_); // std::string value(value_size, 'a'); // db->Put(writeOptions, key, value); // } //} //void InsertData(DB *db, uint64_t ttl/* second */) { // WriteOptions writeOptions; // int key_num = data_size / value_size; // srand(static_cast(time(0))); // for (int i = 0; i < key_num; i++) { // int key_ = rand() % key_num+1; // key_ = 1; // std::string key = std::to_string(key_); // std::string value(value_size, 'a'); // db->Put(writeOptions, key, value, ttl); // std::cout << "time to alive" << ttl << std::endl; // break; // } //} void InsertData(DB *db, uint64_t ttl/* second */) { WriteOptions writeOptions; int key_num = data_size / value_size; srand(0); for (int i = 0; i < key_num; i++) { int key_ = rand() % key_num+1; std::string key = std::to_string(key_); std::string value(value_size, 'a'); db->Put(writeOptions, key, value, ttl); //break; } } //int main(){ // DB *db; // // if(OpenDB("testdb", &db).ok() == false) { // std::cerr << "open db failed" << std::endl; // abort(); // } // // uint64_t ttl = 20; // InsertData(db, ttl); // // leveldb::Range ranges[1]; // ranges[0] = leveldb::Range("-", "A"); // uint64_t sizes[1]; // db->GetApproximateSizes(ranges, 1, sizes); // //ASSERT_GT(sizes[0], 0); // assert(sizes[0] > 0); // Env::Default()->SleepForMicroseconds(ttl * 1000000); // // db->CompactRange(nullptr, nullptr); // // leveldb::Range ranges2[1]; // ranges2[0] = leveldb::Range("-", "A"); // uint64_t sizes2[1]; // db->GetApproximateSizes(ranges2, 1, sizes2); // assert(sizes2[0] == 0); //} int main() { DB *db; if(OpenDB("testdb", &db).ok() == false) { std::cerr << "open db failed" << std::endl; abort(); } uint64_t ttl = 20; // InsertData(db, ttl); WriteOptions writeOptions; int key_ = 1; std::string key = std::to_string(key_); std::string value(1, 'a'); db->Put(writeOptions, key, value, ttl); std::cout << "time to alive" << ttl << std::endl; ReadOptions readOptions; std::string value_read; Status status = db->Get(readOptions, key, &value); //std::cout<<"start sleep for " << Env::Default()->SleepForMicroseconds(ttl * 1000000); key_ = 1; key = std::to_string(key_); std::string value_read_second; status = db->Get(readOptions, key, &value_read_second); assert(status.ok() != true); return 0; }