SA-514

Summary

Developers at an offshore site report slowness while working in the Developer portal. They notice errors in the log: java.io.IOException: Async IO operation failed (3), reason: RC: 107 Transport endpoint is not connected. A Fiddler trace shows nothing being sent to the server during this slowness for any UI action. User report this slowness on IE9, working in Chrome is relatively faster.

Error Messages

Not Applicable 

Steps to Reproduce

Work in the Developer portal for long periods of time.

Root Cause

The root cause of this problem is defect in the IE browser. A bug in IE (present in IE6,7,8,9,10) produces an AJAX error a significant percentage of the time for a network with high latency between the Browser and the Server. The greater the latency, the more frequent the error.

What happens is that the Webserver starts to (correctly) close the connection because the KEEPALIVE interval on the connection has expired.Because of the extreme latency between the Webserver and the IE client, it may be quite a long time before the client becomes aware of the connection is closing. During this time, the client issues a POST request which fails because the connection is closed on the other end.

Resolution

A fix to address this issue has been implemented in Pega 7.1.6.
Developer would also need to use the below script to set a callback timeout in UserWorkForm based on what is suitable for their application.
e.g.
<script type="text/javascript">
pega.u.d.ajaxTimeout = 30000; /* specify a time oout what is suitable for their application */
</script>