Instructor Notes

Timing

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Episode	Teaching	Exercises
A shared software stack	15	10
Finding and loading a module	20	20
The EESSI client container	15	15

Teaching is 50 minutes and exercises are 45 minutes. If the room is short on time, keep the CPU-line challenge and the Python 3.13.5 check. Skip the 2023.06 load.

Source

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The environment-modules section of the deck, from the heading “Environment modules” through the Lmod command table, is course-module-fundamentals-of-hpc/slides/fundamentals-of-hpc.org in https://github.com/HaoZeke/introduction-to-supercomputing.

Branch: fix/slides-fundamentals-source

Commit: 2ebb95294418d5831143e393e93b294af39464b1

The course-cluster note on that deck is the slide “This course runs on a course cluster built like Snellius”. The version strings Python/3.13.5-GCCcore-14.3.0 and Python/3.11.5-GCCcore-13.2.0, the init-script transcript, and the two EESSI_* variables are from the software episode this lesson replaces. They are not printed on that slide.

EasyBuild stays a pointer. Book: https://hpceb.rgoswami.me/. Sources: https://github.com/HaoZeke/what-easybuild-is-doing.

What to skip

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Do not open EasyBuild. Do not search the EESSI tree for QCG-PilotJob. Do not download the client image if everyone already has a cluster login. The container episode is then a reading of the two variables and the CPU line.

Common mistakes

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• module load of a second stack in a shell that already has one. module purge comes first.
• Copying a neighbour’s CPU directory into a script. The init script picks the path.
• module spider QCG-PilotJob in the container, then a private install. The tool is a site module. The tab has the load line.
• A long Python script on the login node. python3 --version is the command that belongs there.
• module load 2025 and a second source of the init script in the same shell.
• Expecting sbatch inside the client container.

Prep checklist

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• Confirm which machine the room will use. The tabs differ.
• On a cluster, from a clean shell, module load 2025 then module load Python/3.13.5-GCCcore-14.3.0, and python3 --version prints Python 3.13.5.
• module spider QCG-PilotJob does not find it in a pure EESSI shell. After the site load in the QCG tab, module list shows QCG-PilotJob.
• If you will teach the container live, pull docker://ghcr.io/eessi/client:rocky8 once before the room arrives. Apptainer must be 1.0 or newer and must support --fusemount.
• Decide whether the 2023.06 purge-and-load is in the exercise or only on the board. It needs a shell you can purge.

What to collect

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One python3 --version line that reads Python 3.13.5, and one CPU line from the init script. The CPU name will differ between laptops. That difference is the point.

A shared software stack

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What to skip

Do not open EasyBuild. Do not build a module from a recipe. Point at the book and move on.

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Finding and loading a module

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The EESSI client container

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What to skip

If everyone is already on a cluster, do not spend the time downloading the image. The stack is already mounted. Read the two variable names, show one CPU line, and return to the modules.

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