Neocortex CS

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Neocortex CS is an AI accelerator system consisting of two Cerebras CS-2 wafer-scale engines with an HPE Superdome Flex host for data preparation and job launch. It is particularly well suited for large-scale deep learning training and inference that benefit from wafer-scale AI acceleration rather than conventional GPU training. It is often used for model training, validation, compilation, and evaluation workflows.

Submitting Jobs Documentation

Neocortex CS-2 uses Slurm for interactive and batch workloads. The SDFlex host nodes support data preparation, validation, compilation, training, and evaluation workflows for the Cerebras CS-2 systems.

Before submitting a job, identify the appropriate PSC project and select its Unix group:

projects groups newgrp GRANT_ID

Common Slurm commands include:

squeue -u $USER # Show your queued and running jobs squeue -j JOB_ID # Show one job scancel JOB_ID # Cancel a job scontrol show job JOB_ID # Display detailed job information

Start an interactive job on either available SDF node with:

interact

To request a specific SDF node, use:

srun --nodelist=sdf-1 --pty bash -i

For CPU-based validation or compilation, request an SDF host node and start the PSC-provided Cerebras container:

srun --pty \ --cpus-per-task=28 \ --kill-on-bad-exit \ singularity shell \ --cleanenv \ --bind /local1/cerebras/data,/local2/cerebras/data,/local3/cerebras/data,/local4/cerebras/data,$PROJECT \ /ocean/neocortex/cerebras/cbcore_latest.sif

A CS-2 training or evaluation job must request a Cerebras accelerator. A minimal batch-script header is:

#!/usr/bin/bash #SBATCH --job-name=cs2-job #SBATCH --account=GRANT_ID #SBATCH --time=04:00:00 #SBATCH --gres=cs:cerebras:1 #SBATCH --ntasks=7 #SBATCH --cpus-per-task=14 #SBATCH --output=%x-%j.out newgrp GRANT_ID # Add the Cerebras container and application commands here.

Submit and monitor the script with:

sbatch job.sbatch squeue -u $USER

The documented default wall time for normal interactive and batch jobs is four hours, and the maximum wall time is 48 hours. Reservations may use a different duration when approved by the Neocortex team.

See the instructions for running interactive and batch CS-2 jobs, the complete Neocortex compilation and batch-script examples, and the Neocortex reservation and wall-time instructions.

Queue specifications

Queue CPU cores / node Num nodes Max wallclock
sdf
SDFlex host nodes for CS-2 validation, compilation, training, and evaluation workflows
Intel Xeon Platinum 8280L 2 48h

Software Documentation

No software usage data is currently reported for Neocortex CS in XDMoD.

SEE ALL SOFTWARE AVAILABLE ON NEOCORTEX CS


Storage Documentation

Neocortex uses PSC's persistent /jet and /ocean filesystems for personal and project data. Use $HOME for small personal files, $PROJECT for project data, and $PROJECT/../shared for files shared with project members.

The SDFlex host used by Neocortex CS workflows also provides node-local storage at /local1 through /local4. These locations are temporary and visible only from the SDFlex compute nodes. Use $LOCAL inside jobs and copy important results back to persistent project storage before the job ends.

If you belong to multiple PSC projects, run newgrp <GROUP_ID> before using $PROJECT for the intended allocation.

File System Documentation

Directory Path Quota Purge Backup Notes
Ocean /ocean See notes Shared storage
Project /ocean/projects/<allocation>/<user> See notes Project storage
Jet /jet/home/PSC_USERNAME See notes Home; max quota may block login
Local /local{1..4} See notes Cleared after job Not backed up Temporary high-speed job I/O

External Storage Documentation

Every Neocortex allocation also carries an allocation on Bridges-2 for general-purpose computing, and Neocortex's Home and Projects tiers are the same PSC file systems Bridges-2 uses - so persistent data is reachable from both machines without copying it. See [Bridges-2 File Spaces] for the quotas and layout of those file systems.


File Transfer Documentation

Neocortex provides data transfer nodes for moving data into and out of the Neocortex environment. PSC documents rsync as the preferred method, with scp not recommended and sftp also supported.

Use data.neocortex.psc.edu for command-line transfers to project or shared storage, such as locations under /ocean/projects/<GRANT_ID>/. See the Neocortex Data Management and Storage documentation for current examples.

Supported Methods Data Transfer Node / Globus Collection Notes
RSYNC | RECOMMENDED data.neocortex.psc.edu
SCP data.neocortex.psc.edu
SFTP data.neocortex.psc.edu