http://www.perlmonks.org?node_id=111226


in reply to Re (tilly) 1: flat-file vs DB_File
in thread flat-file vs DB_File

But that doesn't matter for access because you don't sequentially scan through the file, you jump right to the data, ...

If the file page you're jumping to is already in the kernel's disk cache, this is a win. But if getting to the target page requires moving the disk head, you might be better off with a sequential scan. For an infrequently accessed file in the 7-8 disk page range, I suspect that the linear scan might win.

I think we're in the toss-up category.

BTW, this is a tricky one to test by profiling, since you may have to go out of your way to make sure that the file isn't cached.