Mark not sure if this is still relevant at V7R1 and above, but I know we had customers have issues related to IPV6 being enabled for Java. Was causing DNS timeouts like others have mentioned.
Old but maybe still relevant.
http://www-01.ibm.com/support/docview.wss?uid=nas8N1011363
Regards,
Richard Schoen
Director of Document Management
e. richard.schoen@xxxxxxxxxxxxxxx
p. 952.486.6802
w. helpsystems.com
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message: 1
date: Fri, 6 Jul 2018 08:57:41 -0400
from: Mark Murphy <jmarkmurphy@xxxxxxxxx>
subject: JDBC performance issues after moving to Java 8
We have a Java application running on IBM i v7.1. It was working fine with Java 6, but when we moved to Java 8 in preparation for an upgrade to v7.3, the program started taking over an hour to run. As far as I know, the only change was to move to Java 8. We are using the 32 bit JVM for both Java 6 and Java 8.
Any ideas on where to look for issues? We are not getting any errors that I know of, and everything is running through properly. It just takes over an hour for the program to run now when it used to take minutes. The application is using JDBC to communicate with a MS SQL Server. It is basically synchronizing data for another process that runs on Windows.
midrange.com
