Theta OS Upgrade Complete

We have completed the major Theta OS update, upgrading ALCF-Theta from its current SLES12/CNL6 configuration to SLES15/CNL7. This will require some user codes to be rebuilt and/or relinked. We have also upgraded Theta’s Sonexion Lustre filesystem. For more information, including a full list of known improvements and impacts associated with the upgrade, please read the upgrade notes:

Please be aware that the upgrade has changed adaptive routing from “Adaptive 0” to “Adaptive 3". This change will result in positive overall performance improvement for applications especially those that are sensitive to network latency (for more information, visit: If you have questions or feedback on this change and its impact on application performance, please contact at us