Ansys HPC licensing is how Ansys licenses parallel processing for its solvers: running one simulation on more CPU cores, GPUs or GPU compute units (GCUs), or running several design variations at once. Ansys offers several high-performance computing licence options. With FlexNet licences they cannot be combined in one solution, but Ansys HPC or HPC Packs can be combined with Elastic Licensing.[1] HPC licences come on top of the solver licence, which is usually a simultaneous task under a Standard License. The default “Standard License” product code warns that documentation may add restrictions “regarding the number of cores or functionality”.[6] For the general model, see processor and core licensing.
Editions
Ansys names three HPC products for FlexNet licensing, and Elastic HPC for pay-per-use.
| Option | Description | Catalog |
|---|---|---|
| Ansys HPC | Physics-neutral licences that run a simulation across multiple cores and/or GPUs and work with most Ansys applications[1] | Ansys HPC |
| Ansys HPC Pack | Licences combined into predefined packs “to give you greater value and scalability”[2] | Ansys HPC Pack |
| HPC Workgroup | Volume access to parallel processing for multiple jobs and/or users within “a single co-located workgroup”[3] | Rule HPC Packs cannot be split between users or analyses |
| Elastic HPC | Ansys HPC, LS-DYNA HPC, OPTIS HPC and Rocky HPC charged per hour from Ansys Elastic Currency[4] | Ansys Elastic Currency |
Ansys positions HPC licences for “entry-level parallel processing”, where customers “license only parallel processes needed”. HPC Packs are for higher-fidelity simulations that need to scale. HPC Workgroup is for capacity, meaning many multi-core jobs.[3] LS-DYNA is different. Standard anshpc and anshpc_pack licences cannot be used with it, and a run on n cores uses one LS-DYNA licence plus n-1 LS-DYNA HPC (dysmp) licences.[1]
Metrics
Included cores. Most Ansys applications allow four CPU cores without any HPC licence. Ansys HPC licences add cores, GPU cards or GCUs. Running Ansys CFD Enterprise on twelve CPU cores therefore uses eight Ansys HPC licences.[1] The Mechanical APDL guide says that HPC licences add cores to the four included, while HPC Packs “function independently of the four included cores”.[2] Catalog: Four cores included; Ansys HPC licences enable the rest.
GPUs and GCUs. Solvers running on CPUs are licensed per core. Solvers using GPUs may be licensed per GPU card or per GCU. A GCU is a streaming multiprocessor on NVIDIA cards or a compute unit on AMD cards, which Ansys treats like a CPU core for licensing.[1] The Licensing Guide tabulates included cores, GPUs and GCUs per product. For some solvers no more than 50% of the HPC tasks can be used to enable GPUs: two HPC Packs enable 36 cores in total, of which at most 18 can be used for GPUs.[1] The number of HPC licences used depends on GPU cards and GPU engines, not on CUDA cores.[1]
Counting / floors
No mixing, no splitting. Ansys HPC and HPC Packs cannot be used in the same FlexNet solution.[1] An individual HPC Pack licence cannot be split between users or between analyses.[1] Ansys’s HPC page adds that, apart from the four free built-in increments per solver licence, HPC Packs cannot be combined with any other type of HPC licence in the same analysis.[3] A user’s preferences file decides whether HPC Packs or individual HPC licences are used first.[1] Catalog: HPC options cannot be combined in one solution (except with Elastic); HPC Packs cannot be split between users or analyses.
Coupled runs. In a system coupling calculation each solver checks out its own HPC licences. Ansys’s example is Fluent on six cores and Mechanical on eight cores. This needs a CFD solver licence plus an HPC Pack or 2 Ansys HPC licences, and a Mechanical solver licence plus an HPC Pack or 4 Ansys HPC licences.[1]
Parametric variations. Since release 2020 R2, HPC licences can run concurrent parametric variations in place of extra solver licences. Each variation after the first needs 8 HPC increments or 1 HPC Pack increment. Each variation includes 4 parallel cores or GPU SMs, and the licences are held for the whole simulation.[1] The Licensing Guide gives a formula for the increments checked out up front when Workbench’s upfront licence checkout is enabled.[1] Catalog: Concurrent parametric variations: 8 HPC or 1 HPC Pack per extra variation.
Borrowing. HPC licences do not take part in licence borrowing, and only one HPC Pack can be borrowed at a time.[1] Catalog: Borrowing is limited to 30 continuous days and 90 days a year.
Floors. No minimum is published. In practice the floor is the four included cores per solver licence; anything above them needs HPC.[1]
Virtualization & partitioning
Ansys counts logical capacity, not physical sockets. Hyperthreads count in full. A 24-core solution on a CPU with 12 physical and 12 hyperthread cores uses the HPC licences needed for 24 cores. Ansys notes that the hyperthread cores usually add little or no speed, and it does not recommend hyperthreading.[1] GPU partitions count separately. A GPU divided into logical partitions is charged one HPC licence per partition, regardless of how many physical GPUs there are.[2] For a licence manager, the core count to reconcile is the number of cores and partitions the job requested, not the hardware inventory. Catalog: Hyperthread cores count as cores; GPU partitions count as GPUs. See virtualization and partitioning.
Cloud / BYOL
Ansys describes HPC “wherever it runs, on-premises, in the cloud, or across hybrid environments”. It names Ansys Cloud Burst Compute for on-demand HPC inside Ansys applications, and cloud-hosting partners that support both BYOL and pay-per-use Elastic licensing.[3] Under Elastic Licensing, rate table v9 charges Ansys HPC at int(7.3·n^0.57) AEC per hour. Here n is the number of extra CPU cores or GPU compute units requested above those included with the base product. If the base product includes 4 cores and the job uses 8, n is 4.[4] Elastic Licensing does not support HPC Packs, so a pack request is converted into Ansys HPC.[1] Catalog: Elastic HPC is charged by formula int(7.3*n^0.57) AEC per hour.
A worked example from the published formula (commentary, not an Ansys statement): a job using 36 cores on a product with 4 included cores has n = 32. Since 32^0.57 is about 7.2, the job costs int(7.3 × 7.2) = 52 AEC per hour for HPC, on top of the solver’s own hourly rate.
Programs
HPC licences can be bought as Lease or Paid-up licences, like other Ansys products.[5] If TECS is not renewed on perpetual HPC licences, they can only enable multi-core runs of solvers released before TECS expired.[1] An upgrade to a new solver release therefore depends on current TECS for both the solver and the HPC licences. Catalog: TECS; Perpetual HPC without TECS works only with solvers released before TECS expiry.
Out of scope
- The full table of included cores, GPUs and GCUs per product, which is in the Licensing Guide and changes by release.
- HPC Pack and HPC Workgroup prices and pack sizes beyond the Licensing Guide’s examples.
- Hardware rates for Ansys Cloud Direct, which are in a separate hardware consumption table.