Cori for Edison Users
Running jobs on Cori is similar to running jobs on Edison, but there are some differences to remember:
- Cori has a different operating system than Edison. This means that, despite the CPUs being compatible, applications compiled for Edison will need to be recompiled for Cori, in order to link the correct libraries.
- Cori Xeon "Haswell" nodes, accessed with "-C haswell" option of sbatch or salloc, have two sockets and each socket is populated with a 16-core Intel "Haswell" processor at 2.3 GHz for a total of 32 cores per node. Edison has a total of 24 cores per node, each node has two sockets, each socket is populated with a 12-core Intel "Ivy Bridge" processor at 2.4 GHz. On Cori, jobs must specify whether they need Haswell (Xeon) or KNL (Xeon Phi) nodes with "#SBATCH -C haswell" or "#SBATCH -C knl", this is not required on Edison.
- Cori Haswell nodes have 128 GB of memory per node, the STREAM TRIAD bandwidth per node is 120 GB/s. Edison has 64 GB of memory per node, the STREAM TRIAD bandwidth per node is 103 GB/s.
- Both Cori and Edison use Cray Aries with Dragonfly topology for high speed interconnect.
- Cori has only one /scratch file system, referred to as $SCRATCH - which is also mounted on Edison as $CSCRATCH. Edison has 3 scratch file systems, users are given directory under either /scratch1 or /scratch2, referred to as $SCRATCH. Also users can request a /scratch3 directory.)
- Cori has a Burst Buffer, a layer of SSDs that sit inside the HSN and offer very high performance I/O.