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blast+ , blastall

NCBI Blast+ is a shared-memory program that runs on a single node with multiple threads. The Intel processors on the razor cluster will run blast about three times as fast as the AMD processors on trestles (but trestles has twice as many per node). Razor 12-core nodes are sufficient since blast+ scales to about 8 threads as shown by user/real time, but the number of cores present is used in each example. Blast works better with a database located on a local file system, so if doing a number of runs, it may be worth the couple of minutes to copy the database to your area of the local scratch disk, as shown. For a single run it is probably faster overall to specify to blast the parallel filesystem database. If copying the database please remember to remove it at the end of the job.


/home/rfeynman$ cd /local_scratch/rfeynman
/local_scratch/rfeynman$ rsync -a /share/apps/bioinformatics/blast/db20150912/nt .
/local_scratch/rfeynman$ module purge;module load blast/2.3.0+ 
/local_scratch/rfeynman$ time blastn -num_threads 32 -db nt/nt -query /home/rfeynman/NM_001005648 \

real    0m11.146s
user    1m33.556s
sys     0m10.938s
/local_scratch/rfeynman$ rm -rf ./nt

razor: Examples are shown on a 16-core node for the last 3 versions of blastn and for blastall used with qiime. In this case 2.2.29 and 2.3.0 give the same output while 2.2.28 and blastall are different.

/home/rfeynman$ cd /local_scratch/rfeynman
/local_scratch/rfeynman$ rsync -a /share/apps/blast/db/nt .
/local_scratch/rfeynman$ module purge;module load blast/2.2.28+
/local_scratch/rfeynman$ time blastn -num_threads 16 -db nt/nt -query /share/apps/blast/queries/blastn/NM_001005648 >blast-2.2.28.out

real	0m3.273s
user	0m2.204s
sys	0m1.530s
/local_scratch/rfeynman$ module purge;module load blast/2.2.29+
/local_scratch/rfeynman$ time blastn -num_threads 16 -db nt/nt -query /share/apps/blast/queries/blastn/NM_001005648 >blast-2.2.29.out

real	0m3.817s
user	0m38.202s
sys	0m3.077s
/local_scratch/rfeynman$ module purge;module load blast/2.3.0+
/local_scratch/rfeynman$ time blastn -num_threads 16 -db nt/nt -query\
/share/apps/blast/queries/blastn/NM_001005648 >blast-2.3.0.out

real	0m3.327s
user	0m33.666s
sys	0m3.284s
/local_scratch/rfeynman$ module purge
module load gcc/4.6.3 mkl/13.1.0 python/2.7.5 R/3.1.2-mkl qiime/1.9.1
/local_scratch/rfeynman$ time blastall -p blastn -a 16 -d nt/nt -i\ /share/apps/blast/queries/blastn/NM_001005648 -o blastall.out

real	0m6.231s
user	1m20.847s
sys	0m3.195s
/local_scratch/rfeynman$ ls -al *out
-rw-r--r-- 1 rfeynman rfeynman  119520 Feb 29 13:10 blast-2.2.28.out
-rw-r--r-- 1 rfeynman rfeynman  498945 Feb 29 13:11 blast-2.2.29.out
-rw-r--r-- 1 rfeynman rfeynman  498538 Feb 29 13:11 blast-2.3.0.out
-rw-r--r-- 1 rfeynman rfeynman 1422859 Feb 29 13:14 blastall.out
/local_scratch/rfeynman$ diff -ibw blast-2.2.29.out blast-2.3.0.out
< BLASTN 2.2.29+
> BLASTN 2.3.0+
/local_scratch/rfeynman$ rm -rf ./nt
blast.1469136506.txt.gz · Last modified: 2016/07/21 21:28 by root