AR-2020-21

160 33 rd ANNUAL REPORT 2020-21 High Performance Computing HPCClusters Listed inTop Supercomputers in India IUCAA currently has three major independent HPC clusters dedicated to different applications, namely Pegasus, Sarathi andVroom. The Pegasus Cluster is to serve the general computing requirement of the astronomy community associated with IUCAA. It has 60 compute nodes, each with 32 cores and 384 GB RAM. It uses infiniband EDR (100Gbps) as an inter-connect, and Portable Batch System (PBS) as a job scheduler. For visualisation purposes, there are two dedicated graphics nodes equipped with NVIDIA Tesla P100 GPU cards. The cluster is attached to a 2 PB parallel file system (Lustre), which is capable of delivering 15GBps throughput. Theoretical computing speed of the Pegasus Cluster is 100 TF. The Pegasus cluster has been utilized by about 50 high volume users from IUCAAand various Indian Universities, running applications for Molecular Scattering, Molecular Dynamics, Stellar Dynamics, Gravitational N-Body Simulations, Cosmic Microwave Background Evolution, Fluid Mechanics, Magnetohydrodynamics, Plasma Physics, and the analysis of diverse astronomical data. The Sarathi Cluster is primarily used for gravitational wave research and is mostly used by national and international members of the LIGO Scientific Collaboration (LSC), which includes many IUCAA members and associates. The cluster is comprised of heterogeneous compute servers, it is built in three phases. The cluster consists of more than 8000 physical cores. The theoretical peak performance of the compute node CPUs of the cluster is nearly 530 TF. The cluster has 2PiB PFS storage with 30Gbps write and read (1:1) throughput. The Vroom cluster is used solely for the MeerKATAbsorption Line Survey (MALS). This cluster has 16 compute nodes (DELL), which delivers 25 TF computing speed and has a parallel file system (DDN) of 2.5 PB usable capacity attached to it. nd nd th Sarathi Cluster Phase III, Pegasus Cluster, and Sarathi Cluster Phase II are listed at 22 , 32 and 35 rank respectively in the list of top Supercomputers in India published on January 31, 2021. The list is maintained and supported by CDAC's Terascale Supercomputing Facility (CTSF), CDAC, Bengaluru. The list is available at http://topsc.cdacb.in/jsps/jan2021/index.html