blastn Error: mdb_env_open: Cannot allocate memory

Question

[Mehmet]

Dear All,

I downloaded nt database using wget ftp://ftp.ncbi.nlm.nih.gov/blast/db/nt.*.tar.gz it has 115 nt files.

I run blastn using a genome file to the nt database but I received the error below:

Error: mdb_env_open: Cannot allocate memory

I tried different versions of blastn (2.9.0, 2.15) but nothing changed.

The command I used is :

blastn -db ~/Databases/Blast_nt/nt -out A.genome.blast -query A.genome.fa

I tried to increase memory using the command below:

export BLASTDB_LMDB_MAP_SIZE=100000000

Nothing changed. Any solution or suggestion ?

[GenoMax]

How much memory do you actually have? NT will require tens of GB of RAM.

[Mehmet]

I used 900 GB. I run the command on clusters.