Aria2c parallel download parameters

I found the best way to download concurrently via aria2

`aria2c -c -s 16 -x 16 -k 1M -j 1 -i dl.txt`


-c, --continue [true|false]
-s, --split=<N>
-x, --max-connection-per-server=<NUM>
-k, --min-split-size=<SIZE>
-j, --max-concurrent-downloads=<N>
-i, --input-file=<FILE>

NOTE: Downloads the URIs listed in FILE. You can specify multiple sources for a single entity by putting multiple URIs on a single line separated by the TAB and CR(Enter) character.

-s: how many mirrors to use to download each file, mirrors should be listed in one line
-j: how many files (lines in the input file) to download simultaneously
-x: how many streams to use for downloading from each mirror.

So, if it is just one file, it goes like this:

aria2 -d ./ -x 10 "ftp://ftp.sra.ebi.ac.uk/vol1/fastq/ERR209/ERR209558/ERR209558_1.fastq.gz"

If you need to download a number of files, use -i to feed the input file, then go like this:

aria2 -d ./aria_dl/ -x 16 -j 16 -i ./aria_list_of_files.txt

That implies that you have only one link in each line, and aria2 will use 16 streams for each of 16 files it is downloading. If you have multiple mirrors, put all mirrors for each file in one line and add -s N, where N is the maximum number of mirrors.