Go to Environment > Servers > your_Server > Tuning, under Advanced, set the Muxer Class based on your OS and reboot the server.
Solaris/HPUX Native Muxer : weblogic.socket.DevPollSocketMuxer
POSIX Native Muxer : weblogic.socket.PosixSocketMuxer
Windows Native Muxer : weblogic.socket.NTSocketMuxer
Java Muxer : weblogic.socket.JavaSocketMuxer
Solaris/HPUX Native Muxer : weblogic.socket.DevPollSocketMuxer
POSIX Native Muxer : weblogic.socket.PosixSocketMuxer
Windows Native Muxer : weblogic.socket.NTSocketMuxer
Java Muxer : weblogic.socket.JavaSocketMuxer
java.lang.Thread.State: RUNNABLE
at sun.nio.ch.EPollArrayWrapper.epollWait(Native Method)
at sun.nio.ch.EPollArrayWrapper.poll(EPollArrayWrapper.java:269)
at sun.nio.ch.EPollSelectorImpl.doSelect(EPollSelectorImpl.java:79)
at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:87)
locked <0x0000000789f2b040> (a sun.nio.ch.Util$2)
locked <0x0000000789f2b030> (a java.util.Collections$UnmodifiableSet)
locked <0x0000000789f2adf8> (a sun.nio.ch.EPollSelectorImpl)
at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:98)
at weblogic.socket.NIOSocketMuxer$NIOInputStream.readInternal(NIOSocketMuxer.java:815) at weblogic.socket.NIOSocketMuxer$NIOInputStream.read(NIOSocketMuxer.java:759)
at weblogic.socket.NIOSocketMuxer$NIOInputStream.read(NIOSocketMuxer.java:742)
at weblogic.socket.JSSEFilterImpl.readFromNetwork(JSSEFilterImpl.java:462)
at weblogic.socket.JSSEFilterImpl.read(JSSEFilterImpl.java:424)
at weblogic.socket.JSSESocket$JSSEInputStream.read(JSSESocket.java:64) 0x0000000789f2adf8>0x0000000789f2b030>0x0000000789f2b040>