Biowulf High Performance Computing at the NIH
Lumpy on Biowulf

Lumpy detects structural variants from high throughput sequencing data using read-pair, split read, and other signals in parallel.

There are two ways of using lumpy:

Either way, lumpy expects input alignments as created by bwa mem.


Important Notes

Interactive job
Interactive jobs should be used for debugging, graphics, or applications that cannot be run as batch jobs.

Allocate an interactive session and run the program. Sample session:

[user@biowulf]$ sinteractive
salloc.exe: Pending job allocation 46116226
salloc.exe: job 46116226 queued and waiting for resources
salloc.exe: job 46116226 has been allocated resources
salloc.exe: Granted job allocation 46116226
salloc.exe: Waiting for resource configuration
salloc.exe: Nodes cn3144 are ready for job

[user@cn3144 ~]$ module load lumpy

[user@cn3144 ~]$ lumpyexpress -t2 -B /path/to/input.bam
Sourcing executables from
/usr/local/apps/lumpy/0.2.11/bin/lumpyexpress.config ...

Checking for required python modules
samblaster: Version 0.1.22
samblaster: Inputting from stdin
samblaster: Outputting to stdout
samblaster: Opening gcat_set_053.bam.vcf.Kzd6atukx0F1/disc_pipe for write.
samblaster: Opening gcat_set_053.bam.vcf.Kzd6atukx0F1/spl_pipe for write.
samblaster: Loaded 25 header sequence entries.
samblaster: Output 27571 discordant read pairs to gcat_set_053.bam.vcf.Kzd6atukx0F1/disc_pipe
samblaster: Output 0 split reads to gcat_set_053.bam.vcf.Kzd6atukx0F1/spl_pipe
samblaster: Marked 0 of 39432108 (0.00%) read ids as duplicates using 1188k memory in 1M36S(96.300S) C
PU seconds and 19M47S(1187S) wall time.
Removed 5 outliers with isize >= 404
Running LUMPY... 
chrM    1000000

[user@cn3144 ~]$ lumpyexress -h
usage:   lumpyexpress [options]

     -B FILE  full BAM file(s) (comma separated) (required)
     -S FILE  split reads BAM file(s) (comma separated)
     -D FILE  discordant reads BAM files(s) (comma separated)
     -o FILE  output file [fullBam.bam.vcf]
     -x FILE  BED file to exclude
     -P       output probability curves for each variant
     -m INT   minimum sample weight for a call [4]
     -r FLOAT trim threshold [0]
     -T DIR   temp directory [./output_prefix.XXXXXXXXXXXX]
     -t N     number of threads [1]
     -k       keep temporary files

     -K FILE  path to lumpyexpress.config file
                (default: same directory as lumpyexpress)
     -v       verbose
     -h       show this message

[user@cn3144 ~]$ exit
salloc.exe: Relinquishing job allocation 46116226
[user@biowulf ~]$

Batch job
Most jobs should be run as batch jobs.

Create a batch input file (e.g. For example:


module load lumpy || exit 1
lumpyexpress -t $SLURM_CPUS_PER_TASK -B input.bam -o output.vcf

Submit this job using the Slurm sbatch command.

sbatch --cpus-per-task=10 --mem=10G
Swarm of Jobs
A swarm of jobs is an easy way to submit a set of independent commands requiring identical resources.

Create a swarmfile (e.g. lumpy.swarm). For example:

lumpyexpress -t $SLURM_CPUS_PER_TASK -B input1.bam -o output1.vcf
lumpyexpress -t $SLURM_CPUS_PER_TASK -B input2.bam -o output2.vcf
lumpyexpress -t $SLURM_CPUS_PER_TASK -B input3.bam -o output3.vcf

Submit this job using the swarm command.

swarm -f lumpy.swarm -g 10 -t 10 --module lumpy
-g # Number of Gigabytes of memory required for each process (1 line in the swarm command file)
-t # Number of threads/CPUs required for each process (1 line in the swarm command file).
--module lumpy Loads the lumpy module for each subjob in the swarm