Comment 11 for bug 343371

"echo 1 > queue_depth" was not enought in my case.

What you see in queue_type when you do that?
"simple", "none" or something else?

I resolved it adding my hd (WDC WD3200BEVT-22ZCT0) in the NCQ blacklist
in drivers/ata/libata-core.c and now I can read very big files from the disk
without any problem...

After some test I think 381300 is something
different and you can ignore it...