IRC, freenode, #hurd, 2011-07-22

<braunr> an interesting question i've had in mind for a few weeks now is
  I/O accounting
<braunr> what *is* I/O on a microkernel based system ?
<braunr> can any cross address space transfer be classified as I/O ?

IRC, freenode, #hurd, 2011-07-29

< braunr> how does the hurd account I/O ?
< youpi> I don't think it does
< youpi> not an easy task, actually
< youpi> since gnumach has no idea about it
< braunr> yes
< braunr> another centralization issue
< braunr> does network access count as I/O on linux ?
< youpi> no
< braunr> not even nfs ?
< youpi> else you'd get 100% for servers :)
< braunr> right
< youpi> nfs goes through vfs first
< braunr> i'll rephrase my question
< youpi> I'd need to check but I believe it can check nfs
< braunr> does I/O accounting occur at the vfs level or block layer ?
< youpi> I don't know, but I beleive vfs
< youpi> (at least that's how I'd do it)
< braunr> i don't have any more nfs box to test that :/
< braunr> personally i'd do it at the block layer :)
< youpi> well, both
< youpi> so e2fsck can show up too
< braunr> yes
< youpi> it's just a matter of ref counting
< youpi> apparently nfs doesn't account
< youpi> find . -printf "" doesn't show up in waitio
< braunr> good
< youpi> well, depends on the point of view
< youpi> as a user, you'd like to know whether your processes are stuck on
  i/o (be it disk or net)
< braunr> this implies clearly defining what io is