ecryptfs team mailing list archive

[Theodore Ts'o <tytso@xxxxxxx>]

@Brian,

One other thought... emacs (and all other competently implemented
editors) will use fsync() and *should* use fsync because for networked
filesystems, fsync() may be the only way that the editor will know
whether or not a file will be written to stable storage.   For example,
if AFS returns a quota error, or the NFS server has disappeared because
of a network outage, the OS may not try to contact the fileserver when
calling write(2), and perhaps not even when close(2) is called.  The
only way to be certain of receiving error return codes from file systems
is to call fsync() on the file, before it is closed.   Given the
semantics of fsync(), that will wake up the hard drive, and there's not
much that can be done about that.

If you really don't like that, not saving your buffers will have the
same net effect, and have the same downside risks (namely, that after a
crash, you'll lose data that hasn't been safely written to disk).  Of
course, I use carefully selected hardware (an X61s with integrated
graphics) and I've but rarely had crashes that would have lost me data
--- and I can count the times when I've lost data due to delayed
allocation on the fingers on one hand --- but again, I use the "sync"
command before I do somethng which I think might trigger a kernel crash,
and this is larlgely never been a problem with me.

-- 
Ext4 data loss
https://bugs.launchpad.net/bugs/317781
You received this bug notification because you are a member of eCryptfs,
which is subscribed to ecryptfs-utils in ubuntu.

Status in “ecryptfs-utils” source package in Ubuntu: Invalid
Status in “linux” source package in Ubuntu: Confirmed
Status in ecryptfs-utils in Ubuntu Jaunty: Invalid
Status in linux in Ubuntu Jaunty: Confirmed

Bug description:
I recently installed Kubuntu Jaunty on a new drive, using Ext4 for all my data.

The first time i had this problem was a few days ago when after a power loss ktimetracker's config file was replaced by a 0 byte version . No idea if anything else was affected.. I just noticed ktimetracker right away.

Today, I was experimenting with some BIOS settings that made the system crash right after loading the desktop. After a clean reboot pretty much any file written to by any application (during the previous boot) was 0 bytes.
For example Plasma and some of the KDE core config files were reset. Also some of my MySQL databases were killed...

My EXT4 partitions all use the default settings with no performance tweaks. Barriers on, extents on, ordered data mode..

I used Ext3 for 2 years and I never had any problems after power losses or system crashes.

Jaunty has all the recent updates except for the kernel that i don't upgrade because of bug #315006

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
NonfreeKernelModules: nvidia
Package: linux-image-2.6.28-4-generic 2.6.28-4.6
ProcCmdLine: root=UUID=81942248-db70-46ef-97df-836006aad399 ro rootfstype=ext4 vga=791 all_generic_ide elevator=anticipatory
ProcEnviron:
 LANGUAGE=
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.28-4.6-generic
SourcePackage: linux