The three supercomputing clusters Cirrus, Stratus, and Nebula were installed in the end of 2018 to support the official duties of SMHI in Sweden, MET in Norway, and FMI in Finland within MetCoOp (the meteorological co-operation on operational numerical weather prediction in the Nordic countries).

Cirrus and Stratus deliver more than double the computational performance of the previous Frost and Alvin clusters at NSC, while using only about 25% more power. The main purpose of Cirrus and Stratus is to provide computing power for operational numerical weather prediction, while the Nebula cluster is used for research and development, primarily for MET Norway. Together with the Teho and Voima systems at FMI in Finland, these clusters form the HPC infrastructure for operational weather forecasting for MetCoOp.

All of the clusters are operated by NSC, but the Cirrus cluster is located at SMHI in Norrköping for improved redundancy. Stratus and Nebula are located in Linköping at NSC.

Cluster information

The cluster was delivered and installed by Clustervision BV, using mostly Intel components (servers, CPUs network, and SSDs).

Location SMHI in Norrköping
Compute nodes 256 (248 thin, 8 fat)
Total number of cores 8,192
Estimated max. power Ca. 115 kW
Fast network Intel OmniPath 100 Gbit/s with 48-port leaf and spine switches
Global storage IBM Spectrum Scale GPFS-based storage appliance (ca 1.0 PB)

How to log in

The Cirrus login nodes are called and

Please see the general instructions on getting started for information on how to login for the first time and set your permanent password. Further information available in the Cirrus getting started guide.

Compute Nodes

The compute nodes of Cirrus, Stratus and Nebula are equipped with:

Server model Intel HNS2600BPB with Intel H2204XXLRE 2U/4-node chassis
CPU:s 2x Intel Xeon Gold model 6130 at 2.1 GHz (16 cores each)
L2/L3 cache 1 MiB/core L2 cache, 44 MiB per socket L3 cache
Memory (thin) 96 GiB DDR4 2666 Mhz dual rank memory
Memory (fat) 384 GiB DDR4 2666 Mhz dual rank memory
Disk (thin) 240 GiB SSD (Intel DC S4500)
Diskt (fat) 960 GiB SSD (Intel DC S4500)

Who can use Cirrus?

Access to Cirrus is granted by SMHI or by MET Norway.

User Area

User support

Guides, documentation and FAQ.

Getting access

Applying for projects and login accounts.

System status

Everything OK!

No reported problems


NSC Express