Known Issues HPC3

Below is a list issues that we're actively working on. We hope to have these resolved soon. This is intended to be a temporary page.

For differences between the new platforms and Mahuika, see the more permanent differences from Mahuika.

Recently fixed

New login node "login03" fixes previous performance problems.
Most of the Milan compute nodes are now available, though not yet for multi-node jobs. That includes the 4 nodes with the 80GB A100 GPUs.
MaxRSS is now the same number as it was on the old cluster - just the ordinary (ie: "anon") memory use without caches etc.

Access¶

OnDemand (including Jupyter)¶

The resources dedicated to interactive work via a web browser are smaller, and so computations requiring large amounts of memory or many CPU cores are not yet supported.

Slurm jobs can be submitted, but only from the Clusters > NeSI HPC SHell Access dropdown menu which opens a standard terminal window in the browser. Watch a demo here.

Authentication¶

Currently, when logging into the new platform using a proxy you will be prompted for authentication twice, unless you have set up an ssh key.

MobaXterm¶

The session login process of MobaXterm is not compatible with Tuakiri 2-factor authentication.

ssh through a terminal will still be possible with MobaXterm, but it is recommended to use OnDemand for file browsing, file transfer (for files under 9.8 GB) and terminal access if you would normally have used MobaXterm. Watch a demo of how to use MobaXterm on the new platform.

Software¶

As was already the case on the Milan nodes in Mahuika (where they had a Rocky 8 OS), some of our environment modules cause system software to stop working, e.g: load module load Perl and svn stops working. This is usually the case if they load LegacySystem/7 as a dependency. The solutions are to ask us to re-build the problem environment module, or just don't have it loaded while doing other things.

QChem and any other software using node locked licences won't work on nodes which are not yet registered with that license.

Delft3D_FM wasn't working in Mahuika's Milan partition so probably needs rebuilding.

MPI software using 2020 or earlier toolchains eg intel-2020a, may not work correctly across nodes. Trying with more recent toolchains is recommended eg intel-2022a.

Please let us know if you find any additional problems.

Slurm¶

Compute nodes¶

None of the 3 Mahuika hugemem nodes are present yet, but the largest of the new Genoa nodes do have 1.5 TB of memory.

Jobs in the milan partition are currently limited to one node and 7 days.

GPUs¶

If you request a GPU without specifying which type of GPU, you will get a random one. So please always specify a GPU type.

$TMPDIR¶

On most of the Genoa nodes the size limit on this per-job in-memory directory is currently only 70 TB per node in total across all jobs. So if you need to use more than about 5 TB of it per node then please use --partition=milan to avoid the Genoa nodes or --gres=ssd to get your job's $TMPDIR placed on a fast SSD instead.

BadConstraints¶

This uninformative message can appear as a reason for a job pending in the squeue output when the job is submitted to both milan and genoa partitions (which is the default behaviour). It does not appear to reflect a real problem though, just a side-effect of the mechanism we are using to target jobs to the right-sized node(s).

email¶

Slurm option --mail-type is not yet effective.

ssh into Slurm jobs¶

You cannot yet ssh into most of the the Genoa compute nodes, even if you are running jobs there. That will break any software which depends on ssh to reach remote compute nodes.

WEKA Filesystems¶

From most of the Genoa compute nodes, the cluster-wide filesystems (/home, /nesi/project, /nesi/nobackup, and /opt/nesi) are not yet as fast as they should be.