PLINQ查询和LINQ查询也就是并行和串行的区别:
基本类:
public class Student
{
public int Id { get; set; }
public string Name { get; set; }
public int Age { get; set; }
public DateTime CreateTime { get; set; }
}
具体实现演变:
public partial class Program
{
private static void Sample04()
{
//线程安全字典
var students = new ConcurrentDictionary<int, Student>();
// 并行生成1000万条数据
Parallel.For(0, 10_000_000, (i) =>
{
var single = new Student
{
Id = i,
Name = "name" + i,
Age = i % 100,
CreateTime = DateTime.Now.AddSeconds(i)
};
students.TryAdd(i, single);
});
Console.WriteLine("数据已生成");
// PLINQ查询
var watch = new Stopwatch();
watch.Start();
var query1 = (from n in students.Values.AsParallel()
where n.Age > 18 && n.Age < 80
select n).ToList();
watch.Stop();
Console.WriteLine("PLINQ耗时:{0}", watch.ElapsedMilliseconds);
// LINQ查询
watch.Restart();
var query2 = (from n in students.Values
where n.Age > 18 && n.Age < 80
select n).ToList();
watch.Stop();
Console.WriteLine("LINQ耗时:{0}", watch.ElapsedMilliseconds);
}
private static void LinqTread()
{
var students = new ConcurrentDictionary<int, Student>();
Parallel.For(0, 10, (i) =>
{
var single = new Student
{
Id = i,
Name = "name" + i,
Age = i % 100,
CreateTime = DateTime.Now.AddSeconds(i)
};
students.TryAdd(i, single);
});
Console.WriteLine("数据生成结束");
// 测试PLNQ与LINQ查询
var query = from n in students.Values.AsParallel()
select new {Name = n.Name, ThreadId = Thread.CurrentThread.ManagedThreadId};
foreach (var o in query)
{
Console.WriteLine($"{o} - from ThreadId = {Thread.CurrentThread.ManagedThreadId}");
}
Console.WriteLine($"CurrentThreadId:{Thread.CurrentThread.ManagedThreadId}");
}
}