这个性能测试是错误的还是系统缓存正在以异常的性能工作？
这是我的结果：
[13] 交互次数 100000：63 毫秒
[14] 交互次数 100000：139 毫秒
[12] 交互次数 100000：47 毫秒
[15] 交互次数 100000：44 毫秒
测试结束。
硬件：x86 Family 6 Model 23 Stepping GenuineIntel ~2992 Mhz 3.327 MB, 5.1.2600 Service Pack 3
using System;
using System.Collections.Generic;
using System.Runtime.Caching;
using System.Diagnostics;
using System.Threading;
namespace CacheNet40
{
public class CacheTest
{
private ObjectCache cache;
public CacheTest()
{
cache = MemoryCache.Default;
}
public void AddItem(CacheItem item, double span)
{
CacheItemPolicy cp = new CacheItemPolicy();
cp.SlidingExpiration.Add(TimeSpan.FromMinutes(span));
cache.Add(item, cp);
}
public Object GetItem(string key)
{
return cache.Get(key);
}
}
class Program
{
private static CacheTest Cache = new CacheTest();
private static string allowedChars = "abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ0123456789!@$?_-";
private static int counter = 0;
private static readonly object locker = new object();
static string CreateRandomString(int passwordLength, int idx)
{
char[] chars = new char[passwordLength];
Random rd = new Random((int)DateTime.Now.Ticks + idx);
for (int i = 0; i < passwordLength; i++)
{
chars[i] = allowedChars[rd.Next(0, allowedChars.Length)];
}
return new string(chars);
}
private static void CacheAccessTes()
{
int span = 5;
string key;
string data;
int itens = 1000;
int interactions = 100000;
int cont = 0;
int index = 0;
List<string> keys = new List<string>();
lock (locker)
{
counter++;
}
cont = itens;
//populates it with data in the cache
do
{
key = CreateRandomString(127, Thread.CurrentThread.ManagedThreadId + cont);
keys.Add(key);
data = CreateRandomString(156000, Thread.CurrentThread.ManagedThreadId + cont + 1);
CacheItem ci = new CacheItem(key, data);
Cache.AddItem(ci, span);
cont--;
}
while (cont > 0);
cont = interactions;
index = 0;
//test readings
Stopwatch stopWatch = new Stopwatch();
stopWatch.Start();
do
{
Object ci = Cache.GetItem(keys[index]);
ci = null;
index++;
if (index == itens)
{
index = 0;
}
cont--;
}
while (cont > 0);
stopWatch.Stop();
lock (locker)
{
counter--;
}
string outstring = String.Format("[{0}] number of interactions {1} : {2} milliseconds", Thread.CurrentThread.ManagedThreadId, interactions, stopWatch.ElapsedMilliseconds );
Console.WriteLine(outstring);
}
static void Main(string[] args)
{
for (int threads = 0; threads < 4; threads++)
{
Thread thread = new Thread(new ThreadStart(CacheAccessTes));
thread.Start();
}
Thread.Sleep(1000);
while (true)
{
lock (locker)
{
if (counter == 0) break;
}
Thread.Sleep(100);
}
Console.WriteLine("End of test.");
Console.ReadLine();
}
}
}