I don't know if anyone here use ABYSS for assembly. (or any other assemblers) I have around 45GB fastq file for assembly onto human reference genome using ABYSS. I'm now only running on single processors, and used all 48GB memory on the computer;(48GB is the largest RAM for computer at my institution), and seems it just takes forever to finish.
I'm curious, how much RAM we need to run ABYSS for 45GB input? I googled for a while and found someone said they used like 256GB RAM to run.
And the most advanced machine here is 48GB total RAM, with 24 processors. That means you can use 20+ processors to speed up, but RAM limit is still 48GB. So, suppose we really need 256GB RAM, then even if I run in parallel processors, it still won't work, right?
I used to only mostly play with mapping; for mapping I can split input file if it's too large; but for assembly....
Seems like you should be able to reduce memory footprint by using a smaller value of k for the de Bruijn graph (at the cost of a worse assembly). Have you tried this?
I tried k=25,k=35,k=45; (k=25 is recommended). But seems they are equally memory-costly.