bwa index hs_ref_GRCh37.p5_chr1.fa hs_ref_GRCh37.p5_chr2.fa hs_ref_GRCh37.p5_chr3.fa hs_ref_GRCh37.p5_chr4.fa hs_ref_GRCh37.p5_chr5.fa hs_ref_GRCh37.p5_chr6.fa hs_ref_GRCh37.p5_chr7.fa hs_ref_GRCh37.p5_chr8.fa hs_ref_GRCh37.p5_chr9.fa hs_ref_GRCh37.p5_chr10.fa hs_ref_GRCh37.p5_chr11.fa hs_ref_GRCh37.p5_chr12.fa hs_ref_GRCh37.p5_chr13.fa hs_ref_GRCh37.p5_chr14.fa hs_ref_GRCh37.p5_chr15.fa hs_ref_GRCh37.p5_chr16.fa hs_ref_GRCh37.p5_chr17.fa hs_ref_GRCh37.p5_chr18.fa hs_ref_GRCh37.p5_chr19.fa hs_ref_GRCh37.p5_chr20.fa hs_ref_GRCh37.p5_chr21.fa hs_ref_GRCh37.p5_chr22.fa hs_ref_GRCh37.p5_chrX.fa hs_ref_GRCh37.p5_chrY.fa hs_ref_GRCh37.p5_chrMT.fa hs_ref_GRCh37.p5_unlocalized.fa hs_ref_GRCh37.p5_unplaced.fa -p h_sapiens_37.5 -a iscreates a database (files h_sapiens_37.5*) which takes about 8 minutes but only contains DNA sequences from the first file (hs_ref_GRCh37.p5_chr1.fa
Gareth Wilson suggests tweaking the header lines so that they start with the chromosome number followed by a space and then the full heading.
bwa index /tmp/INPUTS.fa -p h_sapiens_37.5 -a bwtswnow takes 2 hours 23 minutes.
20GB