add rocksdb test code

rocksdb/main.cpp

@@ -0,0 +1,119 @@
+#include <rocksdb/cache.h>
+#include <rocksdb/db.h>
+#include <rocksdb/options.h>
+#include <rocksdb/utilities/optimistic_transaction_db.h>
+#include <rocksdb/utilities/transaction.h>
+#include <rocksdb/utilities/transaction_db.h>
+
+#include <algorithm>
+#include <barrier>
+#include <filesystem>
+#include <format>
+#include <iostream>
+#include <random>
+#include <string>
+
+#include "instant.h"
+
+int main()
+{
+	std::string db_root = "/home/abby/rocksdb_tmp";
+	std::filesystem::remove_all(db_root);
+	rocksdb::Options options;
+	options.disable_auto_compactions = true;
+	options.create_if_missing = true;
+	options.max_write_buffer_number = 10;
+	options.target_file_size_base = 64 << 20;
+	options.write_buffer_size = 64 << 20;
+	options.level0_file_num_compaction_trigger = 500;
+	options.max_bytes_for_level_base = 2 << 30;
+	constexpr size_t count = 100000;
+	constexpr size_t workers = 4;
+	auto ropt = rocksdb::ReadOptions();
+	auto wopt = rocksdb::WriteOptions();
+	std::vector<std::thread> wg;
+	std::vector<std::vector<std::string>> keys {};
+	rocksdb::OptimisticTransactionDB *db;
+	std::cout << "db_root " << db_root << '\n';
+	auto s = rocksdb::OptimisticTransactionDB::Open(options, db_root, &db);
+	assert(s.ok());
+	std::string val(1024, 'x');
+
+	for (size_t tid = 0; tid < workers; ++tid) {
+		std::vector<std::string> key {};
+
+		for (size_t i = 0; i < count; ++i) {
+			auto tmp = std::format("key_{}_{}", tid, i);
+			tmp.resize(1024, 'x');
+			key.push_back(std::move(tmp));
+		}
+		keys.emplace_back(std::move(key));
+	}
+
+	for (size_t tid = 0; tid < workers; ++tid) {
+		auto ks = &keys[tid];
+		wg.emplace_back(
+			[&]
+			{
+				for (auto &x : *ks) {
+					auto kv = db->BeginTransaction(wopt);
+					kv->Put(x, x);
+					kv->Commit();
+					delete kv;
+				}
+			});
+	}
+
+	for (auto &w : wg) {
+		w.join();
+	}
+
+	delete db;
+	wg.clear();
+
+	auto sts =
+		rocksdb::OptimisticTransactionDB::Open(options, db_root, &db);
+	assert(sts.ok());
+	std::barrier g { workers };
+	auto b = nm::Instant::now();
+	std::mutex mtx {};
+	std::atomic<uint64_t> operation { 0 };
+
+	for (size_t tid = 0; tid < workers; ++tid) {
+		auto ks = &keys[tid];
+		wg.emplace_back(
+			[&]
+			{
+				g.arrive_and_wait();
+
+				std::string val;
+				if (mtx.try_lock()) {
+					b = nm::Instant::now();
+					mtx.unlock();
+				}
+
+				for (auto &x : *ks) {
+					auto kv = db->BeginTransaction(wopt);
+					kv->Get(ropt, x, &val);
+					kv->Commit();
+					delete kv;
+				}
+				operation.fetch_add(count,
+						    std::memory_order_relaxed);
+			});
+	}
+
+	for (auto &w : wg) {
+		w.join();
+	}
+
+	printf("thread %ld\niterations %ld\nkey_size %ld\nvalue_size %ld\nops: "
+	       "%.2f\n",
+	       workers,
+	       count,
+	       keys[0][0].size(),
+	       val.size(),
+	       static_cast<double>(operation.load(std::memory_order_relaxed)) /
+		       b.elapse_sec());
+	delete db;
+}