---
title: Introduction
#tags:
#keywords:
last_updated: 28 June 2019
#summary: "Merlin 6 cluster overview"
sidebar: merlin6_sidebar
permalink: /merlin6/introduction.html
redirect_from:
  - /merlin6
  - /merlin6/index.html
---

## About Merlin6

Merlin6 is a the official PSI Local HPC cluster for development and
mission-critical applications that has been built in 2019. It replaces
the Merlin5 cluster.

Merlin6 is designed to be extensible, so is technically possible to add
more compute nodes and cluster storage without significant increase of
the costs of the manpower and the operations.

Merlin6 is mostly based on **CPU** resources, but also contains a small amount
of **GPU**-based resources which are mostly used by the BIO experiments.

### Slurm 'merlin6'

**CPU nodes** are configured in a **Slurm** cluster, called **`merlin6`**, and
this is the _**default Slurm cluster**_. Hence, by default, if no Slurm cluster is 
specified (with the `--cluster` option), this will be the cluster to which the jobs
will be sent.

## Merlin6 Architecture

### Merlin6 Cluster Architecture Diagram

The following image shows the Merlin6 cluster architecture diagram:

![Merlin6 Architecture Diagram]({{ "/images/merlinschema3.png" }})

### Merlin5 + Merlin6 Slurm Cluster Architecture Design

The following image shows the Slurm architecture design for the Merlin5 & Merlin6 clusters:

![Merlin6 Slurm Architecture Design]({{ "/images/merlin-slurm-architecture.png" }})