Hi, I need to test some devices with "almost-sequential" data traffic. This would have anywhere from 10 to 50 I/Os in order then either drop one from the sequence "1 2 3 (no 4) 5 6" or transpose two adjacent ones "1 2 (4 3) 5 6". This could be done with an iolog, but that seems both wasteful (huge files, 131k lines/MB) and slow (for reading and processing the files). To properly test, I need to move something like 3-4 Tb in 8k blocks. It's also inelegant :). It looks like a drop sequence can be done with something like: blocksize=64k rw=write:8k but I'm at a loss for how to do transposition. Could be a hack into the get-next-block code in io_u.c, but I don't see how to actually implement that. Any ideas (or is an iolog the best way)? Thanks, z! Carl Zwanzig -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
