Application testing continued on Derecho last week and the NWSC-3 team deployed a new Spack software stack on the system, which will offer the latest available compilers and libraries from HPE and third-party vendors. Additionally, codes in the NWSC-3 Benchmark Suite were recompiled against the latest software stack. They ran successfully with the exception of one code that triggers a bug in the Lustre file system. Performance tuning of the applications is ongoing and performance is generally meeting expectations. Some tuning work is needed to get the best performance from the Slingshot network interconnect at scale. 

The NWSC-3 team ported the application workload test that will be used during the upcoming Derecho availability test period, and engineers are tuning the workload to balance the application mix across the CPU and GPU nodes. The availability test period will begin when the remaining performance tuning is complete and the Lustre issue is resolved.