Introduction to ARCHER2 for software developers

Key Points

Welcome
  • We should all understand and follow the ARCHER2 Code of Conduct to ensure this course is conducted in the best teaching environment.

  • The course will be flexible to best meet the learning needs of the attendees.

  • Feedback is an essential part of our training to allow us to continue to improve and make sure the course is as useful as possible to attendees.

Connecting to ARCHER2 and transferring data
  • ARCHER2’s login address is login.archer2.ac.uk.

  • The password policy for ARCHER2 is well documented.

  • There are a number of ways to transfer data to/from ARCHER2.

Overview of the ARCHER2 system
  • ARCHER2 consists of high performance login nodes, compute nodes, storage systems and interconnect.

  • There is a wide range of software available on ARCHER2.

  • The system is based on standard Linux with command line access.

ARCHER2 development environment
  • The development environment is controlled through Lmod modules.

  • ARCHER2 supports the GCC and Cray compilers.

  • Compilers are accessed through the ftn, cc and CC wrapper commands.

  • The CSE service can help with software development issues.

ARCHER2 scheduler: Slurm
  • ARCHER2 uses the Slurm scheduler.

  • srun is used to launch parallel executables in batch job submission scripts.

  • There are a number of different partitions (queues) available.

Using resources effectively
  • To use resources effectively, you need to understand the performance of your jobs.

Debugging and profiling on ARCHER2
  • The main debugging tool on ARCHER2 is gdb4hpc

  • The main profiling tool on ARCHER2 is CrayPat

How to be a good ARCHER2 citizen
  • Be careful how you use the login node.

  • Your data on the system is your responsibility.

  • Again, don’t run stuff on the login node.

  • Don’t be a bad person and run stuff on the login node.

Using SAFE
  • SAFE allows you to manage accounts and resources online.

Next steps
  • ARCHER2 has a lot of documentation available.

  • There are lots of training opportunities available.

  • You can get access to ARCHER2 resources via a number of different routes.

Bootstrapping your use of ARCHER2
  • Understand the next steps for you in using ARCHER2.

OPTIONAL PRACTICAL: Benchmarking Molecular Dynamics Performance Using GROMACS
  • Larger systems scale better to large core-/node-counts than smaller systems.