Feature changed by: Karl Eichwalder (keichwa)
Feature #305168, revision 30
Title: Default to relatime
openSUSE-11.1: Rejected by Stanislav Visnovsky (visnov)
reject date: 2008-09-10 10:20:17
reject reason: This is too late for openSUSE 11.1. Postponing.
Priority
Requester: Mandatory
openSUSE-11.2: Done
Priority
Requester: Mandatory
Requested by: Michael Meeks (michael_meeks)
Description:
At least for desktops, we should reduce the memory and I/O thrash
caused by atime updates, by using relatime.
Relations:
- bugreport from community (novell/bugzilla/id: 398616)
https://bugzilla.novell.com/show_bug.cgi?id=398616
- Offers 'noatime' when 'relatime' is clearly better
(novell/bugzilla/id: 461829)
https://bugzilla.novell.com/show_bug.cgi?id=461829
Documentation Impact:
Needs to be documented in release notes
Test Case:
* cat /proc/mounts
* all locally mounted filesystems should have "relatime"
Discussion:
#1: Robert Davies (robopensuse) (2009-01-16 15:52:09)
Bug #461829 is not requesting breaking POSIX semantics by default!
relatime should replace noatime option in the mount options part of
partioner tool, especially now it has been improved to update atime on
file access if it's older than 24 hours.
Standards are important, and LRU file caches cannot be relied on if
noatime usage is common, or if poor backup software touches atimes,
when reading files.
#2: Sven Burmeister (rabauke) (2009-01-23 01:09:47)
11.1 is out and 11.2 getting started. Did anyone hear of ubuntu
suffering from using relatime by default? If not, it seems likely that
there are little to none issues.
#3: Stephan Kulow (coolo) (2009-05-08 16:51:21)
Matthias, I would think the easiest solution is replacing the current
checkbox "use noatime" with "use relatime" and make it default
(possibly per product). atime is a major pain for many systems where
powersave and co are affected.
#4: Matthias Eckermann (mge1512) (2009-05-11 15:52:11) (reply to #3)
I am not perfectly happy, as a system crash could invalide the "atime"s
with "relatime" switched on; looking for supporting information though,
it seems, the broader Linux community is in favour of "relatime" (with
remarkable exceptions); thus I propose:
* introduce "relatime" as an independend parameter
* keep the "noatime" checkbox in YaST
* make "relatime" default on SSDs automatically
* introduce a generic switch in YaST "defaultrelatime", which can be
switched on/off per product
* make "relatime" default "on" for the openSUSE product
Does that help?
#5: Jan Kara (jankara) (2009-05-11 16:33:11)
This is a bit separate to how it will all look in Yast but I wanted to
point out that in current Linus's tree (going to be 2.6.30) is a patch
which changes kernel's default to 'relatime'. So unless we change
something, all filesystems on this or newer kernel are going to be
mounted as relatime (you have to specify 'strictatime' mount option if
you really wish to keep atime).
#6: Stephan Kulow (coolo) (2009-05-12 10:36:27) (reply to #5)
then we can leave everything as it is actually and the feature is Done
once we switch to 2.6.30
#7: Jan Kara (jankara) (2009-05-12 13:08:05) (reply to #6)
Yes, the original request will be fulfilled. But I believe it would be
good to have a selection in partitioner tool like: "Access time
behavior: