1. 测试删除记录操作效率1.1 测试单条记录删除效率 Stopwatch mainStopWatch = new Stopwatch();mainStopWatch.Start();using (var dbContext = new SQLiteDbContext()){ var data = dbContext.Set<Bus>().FirstOrDefault(i => true); if (data != null) dbContext.Set<Bus>().Remove(data); dbContext.SaveChanges();}mainStopWatch.Stop();Console.WriteLine("TestAddAndDeleteHistory - query 1 record and Remove cost " + mainStopWatch.ElapsedMilliseconds + "ms");1.2 测试10条记录删除效率 mainStopWatch.Restart();//原始模式测试删除10条历史记录的效率using (var dbContext = new SQLiteDbContext()){ var datas = dbContext.Set<Bus>().Where(i=>true).Take(10); dbContext.Set<Bus>().RemoveRange(datas); dbContext.SaveChanges();}mainStopWatch.Stop();Console.WriteLine("TestAddAndDeleteHistory - query 10 records and RemoveRange cost " + mainStopWatch.ElapsedMilliseconds + "ms");1.3 测试添加一条记录效率//原始模式测试添加1条历史记录的效率using (var dbContext = new SQLiteDbContext()){ var data = dbContext.Set<Bus>().Add(new Bus() {Id = Guid.NewGuid().ToString(), Name = "11 路", CreateTime = DateTime.Now}); dbContext.SaveChanges();}mainStopWatch.Stop();Console.WriteLine("TestAddAndDeleteHistory - Add 1 records cost " + mainStopWatch.ElapsedMilliseconds + "ms");1.4 测试结果2. 测试多次删除执行效率2.1 测试一：测试单一DbContext删除100次（每次10条记录）效率2.1.1 测试代码mainStopWatch.Restart();//同一个DbContext执行100次删除操作（每次10条记录）花费时间using (SQLiteDbContext db = new SQLiteDbContext()){ for (int i = 0; i < 100; i++) { //lock (lock_ojb) { var datas = db.Set<Bus>().Where(record => true).Take(10); db.Set<Bus>().RemoveRange(datas); db.SaveChanges(); } }}mainStopWatch.Stop();Console.WriteLine("TestAddAndDeleteHistory - Single DbContext RemoveRange 100 times (10 records per time) cost " + mainStopWatch.ElapsedMilliseconds + "ms");2.2 测试二：测试删除100次（每次10条记录），每次删除一个DbContext效率2.2.1 测试代码mainStopWatch.Restart();//执行100次删除操作（每次10条记录）每次一个DbContext花费时间for (int i = 0; i < 100; i++){ using (SQLiteDbContext db = new SQLiteDbContext()) { //lock (lock_ojb) { var datas = db.Set<Bus>().Where(record => true).Take(10); db.Set<Bus>().RemoveRange(datas); db.SaveChanges(); } }}mainStopWatch.Stop();Console.WriteLine("TestAddAndDeleteHistory - RemoveRange 100 times (10 records per time)，" + "one DbContext every time cost "+ mainStopWatch.ElapsedMilliseconds + "ms");2.3 测试结论测试二比测试一效率略高跟单次删除相比，多次删除效率高于单次删除3. 测试单一context多线程添加和删除3.1 测试代码//单一context添加删除多线程测试SQLiteDbContext db = new SQLiteDbContext();var task1 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); //using (SQLiteDbContext db = new SQLiteDbContext()) { for (int i = 0; i < 1000; i++) { db.Set<Bus>().Add(new Bus() {Id = Guid.NewGuid().ToString(), Name = "11 路", CreateTime = DateTime.Now}); db.SaveChanges(); } } stopwatch.Stop(); Console.WriteLine("Single Context Task1 write 1000 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});var task2 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); //using (SQLiteDbContext db = new SQLiteDbContext()) { for (int i = 0; i < 100; i++) { //lock (lock_ojb) { var datas = db.Set<Bus>().Where(record => true).Take(10); db.Set<Bus>().RemoveRange(datas); db.SaveChanges(); } Thread.Sleep(50); } } stopwatch.Stop(); Console.WriteLine("Single Context Task2 write 50 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});Task.WaitAll(task1, task2);db.Dispose();3.2 测试结果：多线程异常4. 测试每个线程一个DbContex的多线程添加和删除记录4.1 测试代码var task1 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); using (SQLiteDbContext db = new SQLiteDbContext()) { for (int i = 0; i < 1000; i++) { db.Set<Bus>().Add(new Bus() {Id = Guid.NewGuid().ToString(), Name = "11 路", CreateTime = DateTime.Now}); db.SaveChanges(); } } stopwatch.Stop(); Console.WriteLine("Using Context Task1 write 1000 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});var task2 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); using (SQLiteDbContext db = new SQLiteDbContext()) { for (int i = 0; i < 100; i++) { //lock (lock_ojb) { var datas = db.Set<Bus>().Where(record => true).Take(10); db.Set<Bus>().RemoveRange(datas); db.SaveChanges(); } } } stopwatch.Stop(); Console.WriteLine("Using Context Task2 Remove 100 * 10 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});Task.WaitAll(task1, task2);4.2 测试结果未出现异常，说明每个线程（上下文）一个DbContext是线程安全的添加一条记录时间330ms左右，跟单独Add相差不大删除一次执行时间1231ms，时间较长，可能收到多线程的影响5. 测试多线程添加和删除，每次操作都Using一个DbContext5.1 测试代码var task1 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); for (int i = 0; i < 1000; i++) { using (SQLiteDbContext db = new SQLiteDbContext()) { db.Set<Bus>().Add(new Bus() {Id = Guid.NewGuid().ToString(), Name = "11 路", CreateTime = DateTime.Now}); db.SaveChanges(); } } stopwatch.Stop(); Console.WriteLine("Using Context Task1 write 1000 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});var task2 = Task.Factory.StartNew(() =>{ Stopwatch stopwatch = new Stopwatch(); stopwatch.Start(); for (int i = 0; i < 100; i++) { using (SQLiteDbContext db = new SQLiteDbContext()) { //lock (lock_ojb) { var datas = db.Set<Bus>().Where(record => true).Take(10); db.Set<Bus>().RemoveRange(datas); db.SaveChanges(); } } } stopwatch.Stop(); Console.WriteLine("Using Context Task2 Remove 100 * 10 records cost = " + stopwatch.ElapsedMilliseconds + "ms");});Task.WaitAll(task1, task2);5.2 测试结论未出现异常添加一条记录时间338ms左右，跟单独Add相差不大删除一次执行时间813ms，时间较长，但比每个线程一个DbContext时间短可能收到多线程的影响