Classification failed without error information

[Chengyao-Peng]

Hi,

I'm using kraken2 to classify my metagenomic reads. For the database, I downloaded a prebuilt kraken database from Struo2 (http://ftp.tue.mpg.de/ebio/projects/struo2/GTDB_release207/kraken2/). The database looks fine as far as I can see.

Then I run kraken2 for taxonomic classification by:

kraken2 W1_R1.fq W1_R2.fq -db GTDB_release207 --output W1_tax.txt --report W1_mpa_tax_report.txt --confidence 0.1 --report-zero-counts --paired --memory-mapping

However, after a few hours, no report is generated. I only got one line from the Stderr: "Loading database information... done." . So basically, the classification failed or didn't start even. Unfortunately I didn't find similar issues posted before. I would really appreciate any ideas about what went wrong there and how to fix it.

Thanks in advance.

Kind regards, Peng