HTCondor vs Slurm Workload Manager

HTCondor is a free high-throughput computing system that coordinates networked machines to run submitted jobs. It finds available machines, matches their resource offers to job requirements and preferences through ClassAds, and can restart a job elsewhere if its current machine becomes unavailable. It is suited to submitting large batches, including thousands of runs across different data sets, and can use otherwise idle machines in a pool. Users do not need login accounts on machines running their jobs; file transfers and split execution support that model. HTCondor can draw on clusters, cloud resources, and international grids, and flocking can connect multiple installations. It supports transfers to and from S3-compatible storage, including Google Cloud Storage through its S3 interoperability API, but not entire buckets or directories. The software is licensed under Apache License 2.0, includes Python bindings, and offers user and administrator guides. Community support is available through a mailing list; paid contract support offers guaranteed resolution and faster turnaround. Security fixes cover current feature and LTS versions, with the previous LTS supported for approximately twelve months after a new LTS release.

Slurm Workload Manager is free, open-source software for allocating compute resources and scheduling work across Linux clusters. It starts and monitors jobs on allocated nodes and manages queues of pending work. Optional plugins add accounting, advanced reservations, gang and backfill scheduling, topology-aware resource selection, resource limits, and multifactor job prioritization. The system uses a central slurmctld manager and slurmd daemons on compute nodes; accounting and REST components are optional. GPU plugins support NVIDIA, AMD, Intel, AWS Trainium, and AWS Inferentia accelerators, along with NVIDIA MPS and GPU sharing. Accounting can use MySQL or MariaDB and can record data in a text file, directly in a database, or through slurmdbd for multiple clusters. Slurmrestd provides REST access, but the API is not designed for direct internet exposure and supports only unencrypted HTTP. Linux is thoroughly tested on arm64, ppc64, and x86_64; FreeBSD and NetBSD support is limited, and macOS is unsupported. Deployment is self-hosted.