[Information] LUMI system upgrade 25.8-8.9

The LUMI system will be offline for maintenance starting on Monday, 25 August, 2025. LUMI login nodes, compute nodes, and all the storage partitions won’t be accessible with the exception of the object storage partition LUMI-O which should remain available during most of the maintenance period. We expect the system to be back in production on Monday, 8 September, 2025.

Significant parts of the system software will be updated in order to get a more stable and up-to-date system after the maintenance break. It includes the base OS (upgraded to SUSE 15 SP6 and the equivalent COS version), and the Slingshot host software. ROCm will be updated to version 6.3 and the programming environment to version 25.03 which is based on ROCm 6.3 and, for the Cray compilers, clang/LLVM 19.

The driver for ROCm 6.3 officially supports ROCm versions from 6.1 onwards, but already benefits from the attempts of AMD to offer a longer support window for ROCm userland libraries on ROCm drivers so should be able to support ROCm versions up to 7.1.

As part of the update, older versions of the Programming Environment up to and including 23.09 that are not fully functional anymore, will be removed from the system.

Users of our containers with AI software should switch now already to the newest versions based on ROCm 6.1 or 6.2 (versions from 2025) as these will likely still work without issues (or with only minor changes) after the update.

Users using the Cray PE should switch to 24.03 (including users of the LUMI software stack). It is the version closest to the 25.03 version that will be offered after the upgrade.

For users with a good understanding of working in a container, we offer containers with the 25.03 programming environments with the Cray, GNU and ROCm compilers. The 25.03 version is based on GCC 14.2, the Cray compilers version 19 and ROCm 6.3 and therefore cannot be used to run GPU software as the current ROCm driver on the system is not yet compatible, but users can already check if their codes compile with these compilers. Information is available here: https://lumi-supercomputer.github.io/LUMI-EasyBuild-docs/c/ccpe/.  The base software stack is almost complete in these containers and some EasyBuild recipes for user-installable software are also already available. You will have to recompile on the final system though.