If you start 300 jobs that have scheduled activities at same time, all socket threads become busy to process these jobs. So, few campaigns do not get dialed for first five minutes and the following exception is logged in the log files:

[SWT-2001-initial-0] ERROR - CallPacer.processMakeCallResponse:263 -
 -----------------------------------------------------
 java.net.SocketTimeoutException: Read timed out
 at java.net.SocketInputStream.socketRead0(Native Method)
 at java.net.SocketInputStream.read(SocketInputStream.java:152)
 at java.net.SocketInputStream.read(SocketInputStream.java:122)
 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)
 at java.io.InputStreamReader.read(InputStreamReader.java:184)
 at java.io.BufferedReader.fill(BufferedReader.java:154)
 at java.io.BufferedReader.readLine(BufferedReader.java:317)
 at java.io.BufferedReader.readLine(BufferedReader.java:382)
 at com.avaya.pim.core.CallPacer.processMakeCallResponse(CallPacer.java:236)
 at com.avaya.pim.core.CallPacer.launchNewCall(CallPacer.java:96)
 at com.avaya.pim.core.CallAction.readyToStartNewAttempt(CallAction.java:383)
 at com.avaya.pim.core.Action.execute(Action.java:1204)
 at com.avaya.pim.core.StateHandler.processContact(StateHandler.java:95)
 at com.avaya.pim.core.StateWorkerThread.run(StateWorkerThread.java:213)