HttpClient call hangs intermittently

Issue

• JBoss access log shows some requests taking several minutes.
• Issue happens intermittently.
• Corresponding thread dump shows the request is making an HttpClient call:

ajp-/1.2.3.4:8009-16" daemon prio=10 tid=0x00007fcf8427a000 nid=0x44c4 runnable [0x00007fcf716d4000]
   java.lang.Thread.State: RUNNABLE
    at java.net.SocketInputStream.socketRead0(Native Method)
    at java.net.SocketInputStream.read(SocketInputStream.java:152)
    at java.net.SocketInputStream.read(SocketInputStream.java:122)
    at org.apache.http.impl.io.AbstractSessionInputBuffer.read(AbstractSessionInputBuffer.java:198)
    at org.apache.http.impl.io.ChunkedInputStream.read(ChunkedInputStream.java:191)
    at org.apache.http.conn.EofSensorInputStream.read(EofSensorInputStream.java:137)
    at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:283)
    at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:325)
    at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:177)
    - locked <0x00000000c9a367f0> (a java.io.InputStreamReader)
    at java.io.InputStreamReader.read(InputStreamReader.java:184)
    at java.io.Reader.read(Reader.java:140)
    at org.apache.http.util.EntityUtils.toString(EntityUtils.java:247)
    at com.example.service.MyService.getSomething(MyService.java:168)