Cache (Önbellek) Teknolojilerinin Okuma Hızları Yönünden Karşılaştırılması

Yazan : Ersin Aksoy
Bilgisayar Yuksek Muhendisi

AMAÇ

Bu çalışmada Memcached, HazelCast, Redis cache mekanizmaları 100 K lik PNG veriler kullanılarak okuma hızlarına göre karşılaştırılmıştır.

YÖNTEM

Önbelleğin (Cache) kullanıldığı ortam Java Servlet olarak belirlenmiştir. 10000 adet key-value kullanılmıştır. Tüm PNG dosyaları Cache lendikten sonra okuma işlemine başlanmıştır. Servlet kodları ekte sunulmuştur.

ÖLÇÜMLER

1- HazelCast PNG OKU

 

 

2- Jedis PNG OKU

3- Memcached PNG OKU

 

SONUÇ

HazelCast ve Memcached okuma hızlarına göre çok yakın sonuçlar vermiş (200 T için 90 ms) tir. Redis benzer koşullarda çok kötü değerler (200 T için 7093 ms) üretmiştir.

 

KAYNAK KODLAR

EK 1 – HAZEL CAST

@WebServlet(name = "Hazel", urlPatterns = {"/Hazel"})
public class Hazel extends HttpServlet {
    private static IMap cache = null;
    private static HazelcastInstance client = null;
    private static Object _synchObject =new Object() ;

    protected void initHazelClient() {
        if (cache == null) {
            synchronized (_synchObject) {
                if (cache == null) {
                    ClientConfig clientConfig = new ClientConfig();
                    clientConfig.getGroupConfig().setName("dev").setPassword("dev-pass");
                    clientConfig.addAddress("localhost");
                    client = HazelcastClient.newHazelcastClient(clientConfig);
                    cache = client.getMap("pngs");
                }

            }

        }

    }

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        initHazelClient();
        response.setContentType("image/png");
        OutputStream out = response.getOutputStream();
        try {

            String path = request.getQueryString();
            byte[] bytes = cache.get(path);
            if (bytes == null) {
                //-------------------
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                FileInputStream fis = new FileInputStream(new File("c:/temp/tile/" + path));
                byte[] buf = new byte[1024];
                int len;
                while ((len = fis.read(buf)) > 0) {
                    baos.write(buf, 0, len);
                }
                fis.close();
                baos.close();

                bytes = baos.toByteArray();
                cache.put(path, bytes);
                //--------
            }

            out.write(bytes);
            out.flush();
        } finally {
            out.close();
        }}

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

 
}

EK 2- MEMCACHED

package cache;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.InetSocketAddress;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.spy.memcached.MemcachedClient;

@WebServlet(name = "Memcached", urlPatterns = {"/Memcached"})
    public class Memcached extends HttpServlet {
 
    private static  MemcachedClient    cache = null;
    private static Object _synchObject=new Object(); 
    
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        
         if (cache == null) {
            synchronized (_synchObject) {
                if (cache == null) {
                       cache = new MemcachedClient( new InetSocketAddress("10.100.1.251", 11211));
                }
            }
        }
         
         response.setContentType("image/png");
        OutputStream out = response.getOutputStream();

        try {
            String path = request.getQueryString();
            byte[] bytes = (byte[]) cache.get(path);
            if (bytes == null) {
                //-------------------
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                FileInputStream fis = new FileInputStream(new File("c:/temp/tile/" + path));
                byte[] buf = new byte[1024];
                int len;
                while ((len = fis.read(buf)) > 0) {
                    baos.write(buf, 0, len);
                }
                fis.close();
                baos.close();

                bytes = baos.toByteArray();
                cache.set(path, 0, bytes);
                //--------
            }
            out.write(bytes);
            out.flush();
        } finally {
            out.close();
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

 
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

}

EK 3- REDIS

package cache;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

@WebServlet(name = "Redis", urlPatterns = {"/Redis"})
public class Redis extends HttpServlet {

   private static final JedisPool jedisPool =  new JedisPool("localhost", 6379);
    private static final Jedis cache = jedisPool.getResource(); 
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
       
               
        response.setContentType("image/png");
        OutputStream out = response.getOutputStream();

        try {
            String path = request.getQueryString();
             byte[] bytes = cache.get(path.getBytes());         
     
            if (bytes == null) {
                //-------------------
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                FileInputStream fis = new FileInputStream(new File("c:/temp/tile/" + path));
                byte[] buf = new byte[1024];
                int len;
                while ((len = fis.read(buf)) > 0) {
                    baos.write(buf, 0, len);
                }
                fis.close();
                baos.close();

                bytes = baos.toByteArray();
              
                
                cache.set(path.getBytes(), bytes);
                //--------
            }

            out.write(bytes);
            out.flush();
        } finally {
            out.close();
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

}