making two io-bound requests in parallel is twice as fast as making them sequentially, only if they don't contend for the same io resource -- bandwidth, disk io

making two io-bound requests in parallel is twice as fast as making them sequentially, only if they don't contend for the same io resource -- bandwidth, disk iops, etc. maybe this is what you mean by independent? but the thing is that in disk io, directory structure is (as far as i know) basically unrelated to relevant contentious resources, when measuring speed maybe if you're doing a billion small files than overhead begins to matter, but copying 3 big files from 3 different directories is gonna take just as long if you do them in parallel vs. if you do them sequentially that may not be true if they're on different disks, but that kind of proves my point, the directory isn't the factor, the underlying disk is > The question is, how independent are IO operations in separate directories. And the article is claiming that they're fairly independent and don't block each other. yeah and in this sense the article is misleading, because (as far as i know) directories are basically unrelated to independence in the general case