心有多大舞臺便有多大

# re: hessian序列化協議+memcached的緩存存取 2008-06-18 10:17 pony

另外附帶說一句,我的經驗,在使用memcached的時候,客戶端在創建socket連接時最好把nagle設置為false.熟悉tcp協議的都知道setTcpNoDelay有什么作用.如果Tcp_NoDelay被設置為true,那么發送數據包時將使用nagle算法對要發送的數據進行緩存處理,只有當達到一定數量之后才把包發送出去,設置為false則立即發送包.對于memcached緩存,一般我們放進去的數據,以及發送的get命令都是很小的包,為了將數據及時傳輸出去,所以要禁用nagle.  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取 2008-06-18 10:35 CHINA BAIDU

不錯1!  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取 2008-06-18 12:19 dennis

@pony
很好的帖子，不知道換成了hession有沒有測試數據？
對于setTcpNoDelay說反了吧？setTcpNoDelay為true，就是設置TCP_NODELAY，也就是禁掉Nagle算法；默認就是false，表示啟用Nagle算法。禁掉Nagle算法可以提高響應性，相應地會降低吞吐量，在這個場景中沒啥必要。



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# re: hessian序列化協議+memcached的緩存存取 2008-06-18 13:24 lizongbo

hession 的序列化效率確實不錯，

不過需要序列化的對象，試過實現java.io.Externalizable接口的方式沒？


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# re: hessian序列化協議+memcached的緩存存取 2008-06-18 13:41 pony

@dennis
測試hessian和java序列化的代碼,寫的不好請見諒^_^
由于把數據存儲到memcached服務器中跟網絡環境,內存有很大關系,跟memcached client設置的參數也有很大關系,所以就不做memcached的存取測試了.

下面的代碼在我的機器上的結果是:
serialize 1000000 users with hessian spend 8 seconds, total size:93000000
serialize 1000000 users with java spend 17 seconds, total size:190000000

/**
* Created at 2008-06-13.
* 測試比較java和hessian的序列化效率.
*/
import java.io.ByteArrayOutputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.Date;

import com.caucho.hessian.io.AbstractHessianOutput;
import com.caucho.hessian.io.Hessian2Output;
import com.caucho.hessian.io.SerializerFactory;

/**
* @author pony
*
* 如果有任何對代碼的修改,請按下面的格式注明修改的內容.
* 序號 時間 作者 修改內容
* 1. 2008-6-13 pony created this class.
*/
public class TestSerializerPerformanceFucntion {
//序列化次數.
private static final int COUNT = 1000000;

private SerializerFactory factory;

public static void main(String[] args) throws Exception {
new TestSerializerPerformanceFucntion().testHessianSerializer();
new TestSerializerPerformanceFucntion().testJavaSerializer();
}

public void testHessianSerializer() throws Exception {
long curr = new Date().getTime();
int size = COUNT;
int len = 0;
for (int i=0; i<size; i++) {
User user = new User();
ByteArrayOutputStream os = new ByteArrayOutputStream();
AbstractHessianOutput out = new Hessian2Output(os);;
SerializerFactory serializerFactory = getSerializerFactory();
out.setSerializerFactory(serializerFactory);
out.startReply();
out.writeObject(user);
out.completeReply();
out.flush();
os.flush();
len += os.size();
out.close();
}
long now = new Date().getTime();
System.out.println("serialize " + size + " users with hessian spend " + (now-curr)/1000 + " seconds, total size:" + len);
}

public void testJavaSerializer() throws Exception {
long curr = new Date().getTime();
int size = COUNT;
int len = 0;
for (int i=0; i<size; i++) {
User user = new User();
ByteArrayOutputStream os = new ByteArrayOutputStream();
new ObjectOutputStream(os).writeObject(user);
os.flush();
len += os.size();
os.close();
}
long now = new Date().getTime();
System.out.println("serialize " + size + " users with java spend " + (now-curr)/1000 + " seconds, total size:" + len);
}

public SerializerFactory getSerializerFactory() {
if (null == factory) {
factory = new SerializerFactory();
}
return factory;
}
}


class User implements Serializable {
/**
* serial Version UID.
*/
private static final long serialVersionUID = -4845300297590675952L;

private String name = "test name";

private Date birthday = new Date();

private int age = 10;

private double money = 1000.56;

/**
* @return the name
*/
public String getName() {
return name;
}

/**
* @param name the name to set
*/
public void setName(String name) {
this.name = name;
}

/**
* @return the birthday
*/
public Date getBirthday() {
return birthday;
}

/**
* @param birthday the birthday to set
*/
public void setBirthday(Date birthday) {
this.birthday = birthday;
}

/**
* @return the age
*/
public int getAge() {
return age;
}

/**
* @param age the age to set
*/
public void setAge(int age) {
this.age = age;
}

/**
* @return the money
*/
public double getMoney() {
return money;
}

/**
* @param money the money to set
*/
public void setMoney(double money) {
this.money = money;
}

/**
* @return the serialVersionUID
*/
public static long getSerialVersionUID() {
return serialVersionUID;
}
}  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取 2008-06-18 13:54 pony

@lizongbo
謝謝!這是個好建議!試過之后,只有驚訝!結果是比hessian的還快了!
運行結果是:
serialize 1000000 users with hessian spend 10 seconds, total size:93000000
serialize 1000000 users with java spend 9 seconds, total size:86000000

把上面代碼中的Serializable 改為
Externalizable,實現下面兩個方法:
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
String name = in.readUTF();
long time = in.readLong();
int age = in.readInt();
double money = in.readDouble();
this.setName(name);
this.setBirthday(new Date(time));
this.setAge(age);
this.setMoney(money);
}

public void writeExternal(ObjectOutput out) throws IOException {
out.writeUTF(name);
out.writeLong(birthday.getTime());
out.writeInt(age);
out.writeDouble(money);
}

不過因為從架構上考慮,我要用php來讀取cache中的內容,所以我希望序列化后的對象能遵循一個統一的協議,所以,我暫時還是要用hessian的方式.  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取 2008-12-04 10:31 LiMengyan

博主能否來個hessian序集？講講hessian部署的結構？我想看看hessian這個服務模塊是怎么給其他應用提供服務的？  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取 2010-09-20 11:00 thebye85

@pony
怎么我這邊測試還是hessian快  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取[未登錄] 2010-10-05 16:38 Jeff

好文章！  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取[未登錄] 2011-06-24 12:03 HK

好文啊！  回復  更多評論   

# re: hessian序列化協議+memcached的緩存存取[未登錄] 2013-12-19 15:40 sa

hessian4.0.7有一個bigdecimal序列化的bug  回復  更多評論