java线程挂起，导致线程池资源耗尽，服务器响应缓慢

[weixin_38051170]

Thread Dump如下： "http-8080-147" daemon prio=10 tid=0x00007fb970216000 nid=0x3792 waiting on condition [0x00007fb7ecfcd000] java.lang.Thread.State: WAITING (parking) at sun.misc.Unsafe.park(Native Method) - parking to wait for <0x000000073e4e0000> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject) at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186) at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2043) at org.apache.http.pool.PoolEntryFuture.await(PoolEntryFuture.java:133) at org.apache.http.pool.AbstractConnPool.getPoolEntryBlocking(AbstractConnPool.java:282) at org.apache.http.pool.AbstractConnPool.access$000(AbstractConnPool.java:64) at org.apache.http.pool.AbstractConnPool$2.getPoolEntry(AbstractConnPool.java:177) at org.apache.http.pool.AbstractConnPool$2.getPoolEntry(AbstractConnPool.java:170) at org.apache.http.pool.PoolEntryFuture.get(PoolEntryFuture.java:102) at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.leaseConnection(PoolingHttpClientConnectionManager.java:244) at org.apache.http.impl.conn.PoolingHttpClientConnectionManager$1.get(PoolingHttpClientConnectionManager.java:231) at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:173) at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:195) at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:86) at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:108) at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82) at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:106) at com.mailu.re.commons.http.NewHttpClientHelper.doGet(NewHttpClientHelper.java:80) 其本质是Servlet调用HttpClient对Solr进行访问。 Solr访问网络没有问题，JDK1.7，Linux ulimit 8K CPU，内存正常。 有6台服务器部署了一样的代码，有一台不会阻塞，配置都是一样的。 请各位大大帮忙指点