what do you record or look for when using these dummy files to test I/O throughput on disk drives. i have no clue and reading from books sure aint helping much.
i know all about the creation and every other thing there is to it but when it comes to actual testing, how do i use them
i was just reading a book that talks about creating large dummy files to test disk transfers and also what will happen if a disk was to fill up. (pretty senseless i think. why would you want to know what will happen when a disk fills up?? wouldn't it disallow any files from being created or eventually crash??)
and when you say try reorganizing the data layout, what do mean?? i mean, how do you do that?? say for instance, from looking at the output of iostat, i determine that a particular disk is being hit really bad with lots of information. how do i rearrange the data on that drive to distribute the data being sent to it so that particular drive do not get hit to death.
I guess the best question here is to ask why you need to do this. I read something similar once in Unix Hints and Hacks (I think...). I've never seen a use for this, other than to test that a drive works OK - like a burn-in period, I guess.