“沒有最優(yōu)，只有平衡”。因此在配置與調(diào)優(yōu)之前，我總喜歡先介紹理論基礎(chǔ)。
Apusic AS V5.1的線程池只是個(gè)池服務(wù)，池中沒有具體的線程，池中管理的線程是與業(yè)務(wù)相關(guān)的服務(wù)啟動(dòng)后并加入的。線程池只負(fù)責(zé)管理池中線程的數(shù)量和生命周期，從而簡(jiǎn)化了Apusic應(yīng)用服務(wù)器的池管理框架。驗(yàn)證線程池的方法有以下幾種：
1. 在Windows下啟動(dòng)Apusic V5.1的mydomain域，里面不帶任何自啟動(dòng)線程的應(yīng)用，在命令行窗口下按Ctrl+Break結(jié)果見附一（各人機(jī)器可能有所不同），發(fā)現(xiàn)系統(tǒng)沒有任何與線程池相關(guān)的線程啟動(dòng)。打開IE訪問一個(gè)HTML頁面，再Ctrl+Break結(jié)果見附二，發(fā)現(xiàn)多了兩個(gè)線程：Running HTTPHandler-1（HTTP服務(wù)線程）和Idle MuxHandler-1（多路復(fù)用服務(wù)線程），Mux空閑是因?yàn)槎嗦窂?fù)用的分配工作已經(jīng)完成，而HTTP忙是因?yàn)镠TTP服務(wù)剛結(jié)束，KeepAlive仍然保持著。可見線程池啟動(dòng)時(shí)是空的，當(dāng)有服務(wù)時(shí)才生成線程加入到池中，池主要負(fù)責(zé)線程的數(shù)量和生命周期。這樣的設(shè)定可以避免受到攻擊時(shí)無限制地創(chuàng)建線程而導(dǎo)致系統(tǒng)宕機(jī)；或者合理使用機(jī)器的性能，平衡分配不同線程池中的線程數(shù)量。
2. 在apusic.conf文件中自定義一個(gè)線程池Test，然后可以在自己的代碼中使用Apusic AS提供的池管理技術(shù)，當(dāng)然如果沒有使用這個(gè)池系統(tǒng)也仍然可以正常運(yùn)行，因?yàn)檫@只是個(gè)池服務(wù)，只是沒有線程加入到池中而已。
<SERVICE
??? CLASS="com.apusic.util.ThreadPoolService"
??? NAME="Apusic:service=ThreadPool,name=Test"
??? >
??? <ATTRIBUTE NAME="MaxThreads" VALUE="150"/>
??? <ATTRIBUTE NAME="Priority" VALUE="5"/>
??? <ATTRIBUTE NAME="ServicePriority" VALUE="H"/>
??? <ATTRIBUTE NAME="IdleTimeout" VALUE="300"/>
??? <ATTRIBUTE NAME="MaxSpareThreads" VALUE="30"/>
??? <ATTRIBUTE NAME="MinSpareThreads" VALUE="5"/>
??? <ATTRIBUTE NAME="MaxQueueSize" VALUE="500"/>
</SERVICE>
3. 只提供default池，其他池都注釋掉，系統(tǒng)依然能夠正常運(yùn)行，也是因?yàn)槌嘏c服務(wù)之間不是緊耦合，沒有的相關(guān)的池，所有的線程統(tǒng)一使用default池，如果有自己的池就通過自定義池處理。
注意：如果有了自定義池，池中線程數(shù)達(dá)到最大值后，系統(tǒng)不會(huì)使用defalut池來處理的，從而充分保證相應(yīng)服務(wù)池的控制。
例如：定義了HTTPHandler池，當(dāng)HTTPHandler線程達(dá)到最大值后，其他只能在Queue中排隊(duì)，如果Queue也滿了，則其他請(qǐng)求將會(huì)被拒絕。
Apusic AS自己使用了五種池：
default：Apusic AS系統(tǒng)默認(rèn)的線程池
MuxHandler：多路復(fù)用的線程池，主要是將請(qǐng)求向不同的服務(wù)，如：HTTP、JMS、ORB等服務(wù)上分配
HTTPHandler：HTTP服務(wù)的線程池
JMSHandler：JMS服務(wù)的線程池
ORBHandler：ORB服務(wù)的線程池
了解了線程池的基本概念，就可以知道在線程池配置中default池最為重要，其他池可以根據(jù)需要增加或者注釋，所有線程池的配置參數(shù)都是相同的，具體的配置參數(shù)解釋如下：
MaxThreads：線程池中能夠運(yùn)行的最大線程數(shù)，也就是提供服務(wù)的線程數(shù)，-1代表無限制
MinSpareThreads，MaxSpareThreads：線程池中最小／最大空閑的線程數(shù)，當(dāng)線程數(shù)符合這個(gè)區(qū)間時(shí)無論空閑多久都不會(huì)被銷毀
IdelTimeout：空閑線程超時(shí)的時(shí)間，超時(shí)后會(huì)如果運(yùn)行的線程總數(shù)大于MaxSpareThreads則被銷毀
Priority（1～10）：受Java線程優(yōu)先級(jí)管理
ServicePriority：服務(wù)啟動(dòng)的優(yōu)先級(jí)，五種（H > A > N > B > L）
MaxQueueSize：當(dāng)所有線程都忙時(shí)，為無法獲得線程的請(qǐng)求提供隊(duì)列進(jìn)行排隊(duì)，Size代表隊(duì)列長度，隊(duì)列滿時(shí)請(qǐng)求被拋棄
Apusic AS的線程池優(yōu)化：
● 一般的WEB應(yīng)用部署在Apusic上時(shí)，不會(huì)用到JMS和ORB服務(wù)，因此可以將這兩個(gè)池注釋掉，減少資源消耗。
● 如果應(yīng)用現(xiàn)階段使用人數(shù)不多，但是伴隨著發(fā)展應(yīng)用人數(shù)會(huì)不斷增長，可以將MinSpareThreads調(diào)整為符合現(xiàn)階段情況的值，將MaxSpareThreads調(diào)整為符合將來的值，這樣系統(tǒng)無須再變動(dòng)就可以有效支持很長一段時(shí)間；
● 如果應(yīng)用一段時(shí)間內(nèi)訪問量變化不大，但是系統(tǒng)偶爾會(huì)遇到高峰訪問，那么可以設(shè)置MinSpareThreads=MaxSpareThreads；
● MaxThreads的值依據(jù)CPU數(shù)量來定，參考值50×CPU核數(shù)，具體值還需要根據(jù)應(yīng)用執(zhí)行過程中對(duì)CPU的壓力決定。
● 關(guān)于Apusic AS V5.1服務(wù)的配置，下篇文章會(huì)單獨(dú)介紹。
附一、
Full thread dump Java HotSpot(TM) Client VM (1.5.0_14-b03 mixed mode, sharing):
"AutoDeployer" prio=6 tid=0x030f2970 nid=0x9e0 in Object.wait() [0x03cef000..0x03cefc6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x23460458> (a com.apusic.deploy.runtime.AutoDeployer)
??????? at com.apusic.deploy.runtime.AutoDeployer.run(Unknown Source)
??????? - locked <0x23460458> (a com.apusic.deploy.runtime.AutoDeployer)
??????? at java.lang.Thread.run(Thread.java:595)
"Thread-4" prio=6 tid=0x031ca7f0 nid=0x21c in Object.wait() [0x0349f000..0x0349fd6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2321c188> (a com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive.run(Util.java:736)
??????? - locked <0x2321c188> (a com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive)
"HTTPSessionSwapper" prio=6 tid=0x031d8168 nid=0xb98 in Object.wait() [0x0345f000..0x0345fa6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2318ba58> (a java.lang.Object)
??????? at com.apusic.web.session.SessionManager$HouseKeeper.run(Unknown Source)
??????? - locked <0x2318ba58> (a java.lang.Object)
"HttpLogger" prio=2 tid=0x031be630 nid=0xfe8 in Object.wait() [0x0341f000..0x0341f9ec]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2317d2b8> (a com.apusic.web.http.HttpLogger)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.apusic.web.http.HttpLogger.getNextRecord(Unknown Source)
??????? - locked <0x2317d2b8> (a com.apusic.web.http.HttpLogger)
??????? at com.apusic.web.http.HttpLogger.run(Unknown Source)
"MuxListener" prio=6 tid=0x031a8be8 nid=0x7dc runnable [0x033df000..0x033dfaec]
??????? at java.net.PlainSocketImpl.socketAccept(Native Method)
??????? at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:384)
??????? - locked <0x23177890> (a java.net.SocksSocketImpl)
??????? at java.net.ServerSocket.implAccept(ServerSocket.java:450)
??????? at java.net.ServerSocket.accept(ServerSocket.java:421)
??????? at com.apusic.net.BlockingListenerThread.run(Unknown Source)
"Timer-0" prio=6 tid=0x031c3b08 nid=0xc98 in Object.wait() [0x0339f000..0x0339fb6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x23133120> (a java.util.TaskQueue)
??????? at java.util.TimerThread.mainLoop(Timer.java:509)
??????? - locked <0x23133120> (a java.util.TaskQueue)
??????? at java.util.TimerThread.run(Timer.java:462)
"LogManager" prio=2 tid=0x02e2c680 nid=0xb20 waiting on condition [0x0335f000..0x0335fbec]
??????? at sun.misc.Unsafe.park(Native Method)
??????? at java.util.concurrent.locks.LockSupport.park(LockSupport.java:118)
??????? at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:
841)
??????? at com.apusic.util.concurrent.LinkedBlockingQueue.take(Unknown Source)
??????? at com.apusic.logging.manager.ServerLogManager$PushThread.dequeue(Unknown Source)
??????? at com.apusic.logging.manager.ServerLogManager$PushThread.run(Unknown Source)
"Low Memory Detector" daemon prio=6 tid=0x00a83bf0 nid=0xa6c runnable [0x00000000..0x00000000]
"CompilerThread0" daemon prio=10 tid=0x00a537b8 nid=0xdc4 waiting on condition [0x00000000..0x02c2f6cc]
"Signal Dispatcher" daemon prio=10 tid=0x00a95a58 nid=0xeb0 waiting on condition [0x00000000..0x00000000]
"Finalizer" daemon prio=8 tid=0x00a50870 nid=0xbd0 in Object.wait() [0x02baf000..0x02bafa6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230d25c8> (a java.lang.ref.ReferenceQueue$Lock)
??????? at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:120)
??????? - locked <0x230d25c8> (a java.lang.ref.ReferenceQueue$Lock)
??????? at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:136)
??????? at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)
"Reference Handler" daemon prio=10 tid=0x00a4f3e8 nid=0xf94 in Object.wait() [0x02b6f000..0x02b6faec]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230d2650> (a java.lang.ref.Reference$Lock)
??????? at java.lang.Object.wait(Object.java:474)
??????? at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
??????? - locked <0x230d2650> (a java.lang.ref.Reference$Lock)
"main" prio=6 tid=0x00038c00 nid=0x718 in Object.wait() [0x0007f000..0x0007fc3c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230e0ed8> (a com.apusic.server.J2EEServer)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.apusic.server.J2EEServer.startup(Unknown Source)
??????? - locked <0x230e0ed8> (a com.apusic.server.J2EEServer)
??????? at com.apusic.server.Main.main(Unknown Source)
"VM Thread" prio=10 tid=0x00a80190 nid=0x490 runnable
"VM Periodic Task Thread" prio=10 tid=0x00a8e780 nid=0xcec waiting on condition
附二、
Full thread dump Java HotSpot(TM) Client VM (1.5.0_14-b03 mixed mode, sharing):
"Running HTTPHandler-1" prio=6 tid=0x02febe58 nid=0xbd8 runnable [0x03d6f000..0x03d6fb6c]
??????? at java.net.SocketInputStream.socketRead0(Native Method)
??????? at java.net.SocketInputStream.read(SocketInputStream.java:129)
??????? at java.io.BufferedInputStream.fill(BufferedInputStream.java:218)
??????? at java.io.BufferedInputStream.read1(BufferedInputStream.java:256)
??????? at java.io.BufferedInputStream.read(BufferedInputStream.java:313)
??????? - locked <0x234dd378> (a java.io.BufferedInputStream)
??????? at com.apusic.web.http.tcp.TCP_BIOProtocol.readLine(Unknown Source)
??????? at com.apusic.web.http.tcp.TCP_BIOProtocol.readRequestLine(Unknown Source)
??????? at com.apusic.web.http.tcp.TCP_BIOProtocol.read(Unknown Source)
??????? at com.apusic.web.http.tcp.TCP_BIOConnection.getNextRequest(Unknown Source)
??????? at com.apusic.web.http.ConnectionHandler.processConnection(Unknown Source)
??????? at com.apusic.web.http.ConnectionHandler.run(Unknown Source)
??????? at com.apusic.util.ThreadPoolImpl$WorkerThread.run(Unknown Source)
"Idle MuxHandler-1" prio=6 tid=0x02cc0d90 nid=0x54c in Object.wait() [0x03d2f000..0x03d2fbec]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x23147df0> (a java.lang.Object)
??????? at com.apusic.util.ThreadPoolImpl.getWork(Unknown Source)
??????? - locked <0x23147df0> (a java.lang.Object)
??????? at com.apusic.util.ThreadPoolImpl$WorkerThread.run(Unknown Source)
"AutoDeployer" prio=6 tid=0x03146980 nid=0x7bc in Object.wait() [0x03cef000..0x03cefc6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2344f8c0> (a com.apusic.deploy.runtime.AutoDeployer)
??????? at com.apusic.deploy.runtime.AutoDeployer.run(Unknown Source)
??????? - locked <0x2344f8c0> (a com.apusic.deploy.runtime.AutoDeployer)
??????? at java.lang.Thread.run(Thread.java:595)
"Thread-4" prio=6 tid=0x031e3868 nid=0xdc8 in Object.wait() [0x0349f000..0x0349fd6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2321c188> (a com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive.run(Util.java:736)
??????? - locked <0x2321c188> (a com.sun.corba.se.impl.javax.rmi.CORBA.KeepAlive)
"HTTPSessionSwapper" prio=6 tid=0x031c1948 nid=0x9f4 in Object.wait() [0x0345f000..0x0345fa6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2318ba58> (a java.lang.Object)
??????? at com.apusic.web.session.SessionManager$HouseKeeper.run(Unknown Source)
??????? - locked <0x2318ba58> (a java.lang.Object)
"HttpLogger" prio=2 tid=0x031b8830 nid=0xb2c in Object.wait() [0x0341f000..0x0341f9ec]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x2317d2b8> (a com.apusic.web.http.HttpLogger)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.apusic.web.http.HttpLogger.getNextRecord(Unknown Source)
??????? - locked <0x2317d2b8> (a com.apusic.web.http.HttpLogger)
??????? at com.apusic.web.http.HttpLogger.run(Unknown Source)
"MuxListener" prio=6 tid=0x02e654a8 nid=0xa28 runnable [0x033df000..0x033dfaec]
??????? at java.net.PlainSocketImpl.socketAccept(Native Method)
??????? at java.net.PlainSocketImpl.accept(PlainSocketImpl.java:384)
??????? - locked <0x23177890> (a java.net.SocksSocketImpl)
??????? at java.net.ServerSocket.implAccept(ServerSocket.java:450)
??????? at java.net.ServerSocket.accept(ServerSocket.java:421)
??????? at com.apusic.net.BlockingListenerThread.run(Unknown Source)
"Timer-0" prio=6 tid=0x02e65c08 nid=0xdf0 in Object.wait() [0x0339f000..0x0339fb6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x23133120> (a java.util.TaskQueue)
??????? at java.util.TimerThread.mainLoop(Timer.java:509)
??????? - locked <0x23133120> (a java.util.TaskQueue)
??????? at java.util.TimerThread.run(Timer.java:462)
"LogManager" prio=2 tid=0x02e2d488 nid=0xbfc waiting on condition [0x0335f000..0x0335fbec]
??????? at sun.misc.Unsafe.park(Native Method)
??????? at java.util.concurrent.locks.LockSupport.park(LockSupport.java:118)
??????? at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1
841)
??????? at com.apusic.util.concurrent.LinkedBlockingQueue.take(Unknown Source)
??????? at com.apusic.logging.manager.ServerLogManager$PushThread.dequeue(Unknown Source)
??????? at com.apusic.logging.manager.ServerLogManager$PushThread.run(Unknown Source)
"Low Memory Detector" daemon prio=6 tid=0x00a83c78 nid=0xc5c runnable [0x00000000..0x00000000]
"CompilerThread0" daemon prio=10 tid=0x00a53910 nid=0x780 waiting on condition [0x00000000..0x02c2f6cc]
"Signal Dispatcher" daemon prio=10 tid=0x00a95ae8 nid=0xc8c waiting on condition [0x00000000..0x00000000]
"Finalizer" daemon prio=8 tid=0x00a50870 nid=0xd10 in Object.wait() [0x02baf000..0x02bafa6c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230d25c8> (a java.lang.ref.ReferenceQueue$Lock)
??????? at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:120)
??????? - locked <0x230d25c8> (a java.lang.ref.ReferenceQueue$Lock)
??????? at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:136)
??????? at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)
"Reference Handler" daemon prio=10 tid=0x00a4f3e8 nid=0x1d0 in Object.wait() [0x02b6f000..0x02b6faec]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230d2650> (a java.lang.ref.Reference$Lock)
??????? at java.lang.Object.wait(Object.java:474)
??????? at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
??????? - locked <0x230d2650> (a java.lang.ref.Reference$Lock)
"main" prio=6 tid=0x00038c00 nid=0x7fc in Object.wait() [0x0007f000..0x0007fc3c]
??????? at java.lang.Object.wait(Native Method)
??????? - waiting on <0x230e0ed8> (a com.apusic.server.J2EEServer)
??????? at java.lang.Object.wait(Object.java:474)
??????? at com.apusic.server.J2EEServer.startup(Unknown Source)
??????? - locked <0x230e0ed8> (a com.apusic.server.J2EEServer)
??????? at com.apusic.server.Main.main(Unknown Source)
"VM Thread" prio=10 tid=0x00a80190 nid=0xab4 runnable
"VM Periodic Task Thread" prio=10 tid=0x00a8e808 nid=0x684 waiting on condition
參考：
http://infocenter.apusic.com/help/index.jsp?topic=/com.apusic.studio.doc.server/output/eclipse/threadpool.html