Ascend
aocc
The AMD Optimizing C/C++ and Fortran Compilers (“AOCC”) are a set of production compilers optimized for software performance when running on AMD host processors using the AMD “Zen” core architecture. Supported processor families are AMD EPYC™, AMD Ryzen™, and AMD Ryzen™ Threadripper™ processors. The AOCC compiler environment simplifies and accelerates development and tuning for x86 applications built with C, C++, and Fortran languages.
Request access
Users who would like to use the Ascend cluster will need to request access. This is because of the particulars of the Ascend environment, which includes its size, GPUs, and scheduling policies.
Motivation
Access to Ascend is done on a case by case basis because:
Ascend SSH key fingerprints
These are the public key fingerprints for Ascend:
ascend: ssh_host_rsa_key.pub = 2f:ad:ee:99:5a:f4:7f:0d:58:8f:d1:70:9d:e4:f4:16
ascend: ssh_host_ed25519_key.pub = 6b:0e:f1:fb:10:da:8c:0b:36:12:04:57:2b:2c:2b:4d
ascend: ssh_host_ecdsa_key.pub = f4:6f:b5:d2:fa:96:02:73:9a:40:5e:cf:ad:6d:19:e5
nccl
The NVIDIA Collective Communication Library (NCCL) implements multi-GPU and multi-node communication primitives optimized for NVIDIA GPUs and Networking. NCCL provides routines such as all-gather, all-reduce, broadcast, reduce, reduce-scatter as well as point-to-point send and receive that are optimized to achieve high bandwidth and low latency over PCIe and NVLink high-speed interconnects within a node and over NVIDIA Mellanox Network across nodes.
Ascend Programming Environment
Compilers
C, C++ and Fortran are supported on the Ascend cluster. Intel, oneAPI, GNU Compiler Collectio (GCC) and AOCC are available. The Intel development tool chain is loaded by default. Compiler commands and recommended options for serial programs are listed in the table below. See also our compilation guide.
Migrating jobs from other clusters
This page includes a summary of differences to keep in mind when migrating jobs from other clusters to Ascend.
Guidance for Pitzer Users
Hardware Specifications
Ascend (PER NODE) | Pitzer (PER NODE) | ||
---|---|---|---|
Regular compute node | n/a |
40 cores and 192GB of RAM 48 cores and 192GB of RAM |
Batch Limit Rules
Memory limit
oneAPI
oneAPI is an open, cross-industry, standards-based, unified, multiarchitecture, multi-vendor programming model that delivers a common developer experience across accelerator architectures – for faster application performance, more productivity, and greater innovation. The oneAPI initiative encourages collaboration on the oneAPI specification and compatible oneAPI implementations across the ecosystem.
Availability and Restrictions
Versions
oneAPI is available on Pitzer, Ascend, and Cardinal. The versions currently available at OSC are:
GSL
GSL is a library of mathematical methods for C and C++ languages.