From 3e7472b3d54853389cd8a17475901fbef976ef18 Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Thu, 1 Sep 2011 09:27:33 +0200 Subject: IRC. --- .../io_accounting.mdwn | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 open_issues/resource_management_problems/io_accounting.mdwn (limited to 'open_issues/resource_management_problems') diff --git a/open_issues/resource_management_problems/io_accounting.mdwn b/open_issues/resource_management_problems/io_accounting.mdwn new file mode 100644 index 00000000..113b965a --- /dev/null +++ b/open_issues/resource_management_problems/io_accounting.mdwn @@ -0,0 +1,49 @@ +[[!meta copyright="Copyright © 2011 Free Software Foundation, Inc."]] + +[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable +id="license" text="Permission is granted to copy, distribute and/or modify this +document under the terms of the GNU Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no Invariant +Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license +is included in the section entitled [[GNU Free Documentation +License|/fdl]]."]]"""]] + +IRC, freenode, #hurd, 2011-07-22 + + an interesting question i've had in mind for a few weeks now is + I/O accounting + what *is* I/O on a microkernel based system ? + 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 -- cgit v1.2.3