It’s been a while since I’ve posted a Little Things Doth Crabby Make entry so here it is, post number 20 in the series. This is short and sweet.
I was eyeing output from the iostat(1) command with the -xm options on a Fedora 17 host and noticed the column headings were weird. I was performing a SLOB data loading test and monitoring the progress. Here is what I saw:
If that looks all fine and dandy then please consider the man page:
OK, so that is petty, I know. But, the series is called Little Things Doth Crabby Make after all. 🙂
Kevin Closson's Blog: Platforms, Databases and Storage 
Sorry I may be just being dumb here but is r/s and w/s the number of read and write requests and not the number of read and written sectors . Are you saying that the headings did not match the expected values ?
Right you are! This is a Little Things Doth Crabby Make post so it made me crabby and that was about it. My main contention with the -x (“extended statistics report”) columns didn’t seem to match the man page. However, upon reconsideration, I think the -x option is allowed to use any columns from the list of “Device Utilization Report” columns because the -x option doesn’t specify what columns it will report. In fact, the man page doesn’t even explicitly say the “extended statistics report” is related at all to the “Device Utilization Report”.
At the end of the day, it probably shouldn’t have made me crabby because the man page is a bit ambiguous in it’s handling of the -x option. I think my eyes were just tired at the moment I was looking at the output. I’ve used the -xm option pair as my go-to for ages and for whatever reason the columns just “looked weird”.
That’s how the Little Things Doth Crabby Make series goes sometimes I guess…