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Salmon

Salmon is a tool for transcript quantification from RNA-seq data.

Salmon is available as a module on Apocrita.

Usage

To run the default installed version of Salmon, simply load the salmon module:

$ module load salmon
$ salmon --help

Usage:  salmon -h|--help or
        salmon -v|--version or
        salmon -c|--cite or
        salmon [--no-version-check] <COMMAND> [-h | options]

Commands:
     index      : create a salmon index
     quant      : quantify a sample
     alevin     : single cell analysis
     swim       : perform super-secret operation
     quantmerge : merge multiple quantifications into a single file

Number of threads

By default, Salmon will run multi-threaded on all available cores. To prevent overloading a compute node, you should override this by passing the p / --threads parameter with the value of ${SLURM_NTASKS} on commands which offer this option.

Example job

Serial job

Here is an example job running on 1 core and 1GB of memory:

#!/bin/bash
#SBATCH -n 1               # (or --ntasks=1) Request 1 core
#SBATCH --mem-per-cpu=1G   # Request 1GB RAM per core
#SBATCH -t 1:0:0           # Request 1 hour runtime

module load salmon

salmon index -t transcripts.fasta \
             -i transcripts_index \
             -p ${SLURM_NTASKS}

salmon quant -i transcripts_index \
             -l A \
             -1 file1.fastq \
             -2 file2.fastq \
             --validateMappings \
             -o transcripts_quant \
             -p ${SLURM_NTASKS}

References