需求：类似于消息推送，在一定时间段内将固定数据发送给用户（用户量很大，抛开技术实现方面问题，只分析异常）
1.异常
[2020-10-28 17:44:03] [INFO] [com.eebbk.onlinelesson.common.util.HttpUtil] [284] - No buffer space available (maximum connections reached?): connect java.net.SocketException: No buffer space available (maximum connections reached?): connect at java.net.DualStackPlainSocketImpl.connect0(Native Method) at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79) at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at java.net.Socket.connect(Socket.java:589) at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:121) at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180) at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:326) at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:605) at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:440) at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:835) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:56) at com.eebbk.onlinelesson.common.util.HttpUtil.doHttpGet(HttpUtil.java:264) at com.eebbk.onlinelesson.common.util.PushMsgUtil.pushMsgWithMachineId(PushMsgUtil.java:127) at com.eebbk.onlinelesson.Call.PushCall.call(PushCall.java:44) at com.eebbk.onlinelesson.Call.PushCall.call(PushCall.java:21) at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) at java.util.concurrent.FutureTask.run(FutureTask.java) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748)
2.异常原因：是因为机器端口号用尽导致tcp无法申请新的端口去建立连接
代码
ExecutorService pool = new ThreadPoolExecutor(20, 20,0L, TimeUnit.MILLISECONDS,
new LinkedBlockingQueue());
try {
List list= liveTelecastService.getStatisticsByActivityKey(coursePackageId+"");
list=new ArrayList<>();
for (int i = 0; i <50000 ; i++) {
list.add("700S520072701");
}
int pushSuccess=0;
Message message = new Message();
//初始化计数器大小
CountDownLatch latch=new CountDownLatch(list.size());
List< Future> futureList=new ArrayList<>();
for (String machineId:list) {
PushCall pushCall = new PushCall(message,machineId,latch);
Future future= pool.submit(pushCall);
futureList.add(future);
}
//等待所有线程执行完成
latch.await();
for (Future future:futureList) {
if(future.get()){
pushSuccess++;
}
}
五万条数据，创建20个线程去请求接口获取数据，根据异常情况，查看代码，频繁new httpclient,每次都要重新建立tcp连接，完成3次握手和4次挥手。
2.修改为http连接池
@Slf4j
public class HttpClientUtils {
// 客户端从服务端读取数据的超时时间
private static final int HTTP_TIMEOUT = 2000;
// 客户端与服务器建立连接的超时时间
private static final int HTTP_CON_TIMEOUT = 200;
// 客户端从连接池中获取连接的超时时间
private static final int HTTP_CON_REQ_TIMEOUT = 1000;
// 路由的默认最大连接
private static final int HTTP_MAX_PERROUTE = 500;
// 整个连接池连接的最大值
private static final int HTTP_MAX_TOTAL = 1000;
private static RequestConfig defaultRequestConfig = null;
private static CloseableHttpClient httpClient = null;
public static CloseableHttpClient getHttpClient()
{
if(null == httpClient)
{
// 创建连接池管理器
PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
// 设置socket配置
SocketConfig socketConfig = SocketConfig.custom()
.setTcpNoDelay(true)
.build();
connManager.setDefaultSocketConfig(socketConfig);
connManager.setMaxTotal(HTTP_MAX_TOTAL);
connManager.setDefaultMaxPerRoute(HTTP_MAX_PERROUTE);
// 设置获取连接超时时间、建立连接超时时间、从服务端读取数据的超时时间
defaultRequestConfig = RequestConfig.custom()
.setSocketTimeout(HTTP_TIMEOUT)
.setConnectTimeout(HTTP_CON_TIMEOUT)
.setConnectionRequestTimeout(HTTP_CON_REQ_TIMEOUT)
.build();
// 创建httpclient实例
httpClient = HttpClients.custom()
.setConnectionManager(connManager)
.setDefaultRequestConfig(defaultRequestConfig)
.build();
}
return httpClient;
}
}
代码
问题解决，不会出现上面的异常。
后记：上面问题解决了，但是由与并发高，又出现了响应超时问题，这个只要设置连接池的超时时间就好
- Read timed out java.net.SocketTimeoutException: Read timed out at java.net.SocketInputStream.socketRead0(Native Method) at java.net.SocketInputStream.socketRead(SocketInputStream.java:116) at java.net.SocketInputStream.read(SocketInputStream.java:171) at java.net.SocketInputStream.read(SocketInputStream.java:141) at org.apache.http.impl.io.SessionInputBufferImpl.streamRead(SessionInputBufferImpl.java:137) at org.apache.http.impl.io.SessionInputBufferImpl.fillBuffer(SessionInputBufferImpl.java:153) at org.apache.http.impl.io.SessionInputBufferImpl.readLine(SessionInputBufferImpl.java:280) at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:138) at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:56) at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:259) at org.apache.http.impl.DefaultBHttpClientConnection.receiveResponseHeader(DefaultBHttpClientConnection.java:163) at org.apache.http.impl.conn.CPoolProxy.receiveResponseHeader(CPoolProxy.java:157) at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:273) at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:125) at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:272) at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:186) at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:89) at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110) at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108) at com.eebbk.onlinelesson.common.util.HttpUtil.doHttpGet(HttpUtil.java:264) at com.eebbk.onlinelesson.common.util.PushMsgUtil.pushMsgWithMachineId(PushMsgUtil.java:127) at com.eebbk.onlinelesson.Call.PushCall.call(PushCall.java:44) at com.eebbk.onlinelesson.Call.PushCall.call(PushCall.java:21) at java.util.concurrent.FutureTask.run$$$capture(FutureTask.java:266) at java.util.concurrent.FutureTask.run(FutureTask.java) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748)
