A graph can sometimes hang and be un-killable if some network connection in it hangs.
Set a shorter
tcp-keepalive so that the connection times out earlier.
The default value on Linux is 2 hours (7,200 seconds).
You can set it to 10 minutes (600 seconds).
The file descriptor can be closed manually using
See How to close file descriptor via Linux shell command.
Certain graphs using SSL-encrypted connections may fail on WebLogic 12 due to damaged library distributed with this application server. The issue can be identified by a SHA-1 digest error in the graph execution stacktrace:
... Caused by: java.io.IOException: Could not convert socket to TLS at com.sun.mail.pop3.Protocol.stls(Protocol.java:659) at com.sun.mail.pop3.POP3Store.getPort(POP3Store.java:269) at com.sun.mail.pop3.POP3Store.protocolConnect(POP3Store.java:207) Caused by: javax.net.ssl.SSLException: java.lang.SecurityException: SHA1 digest error for org/bouncycastle/jce/provider/JCEECPublicKey.class ...
To fix the issue,
replace the library
with the one downloaded directly from
Bouncy Castle home page.
Restart the application server to load the new library.
It may be caused by slow data storage.
vmstat 1 30.
If you see high values under
bo columns, it might be that case.
Another tool to confirm or disconfirm slow data storage as possible cause is