ReiserFS file corruption

ReiserFS file corruption

[Emmanuel Varagnat]

Today, I crashed the kernel and after reboot the source file
I was working on, was completly unreadable. The size indicated
by 'ls' seems to be good but with bad data.

Is this behavior normal (because the FS seems correct) ?
The worst I hoped is loosing the last save, but not everything.

Must I patch to a newer version ?
I'm using a 2.4.3 version.

Thanks

-Manu

PS: Finally I greped the partition and recover my file.

Re: ReiserFS file corruption

[Rasmus Bøg Hansen]

On Mon, 6 Aug 2001, Emmanuel Varagnat wrote:

> 
> Today, I crashed the kernel and after reboot the source file
> I was working on, was completly unreadable. The size indicated
> by 'ls' seems to be good but with bad data.
> 
> Is this behavior normal (because the FS seems correct) ?
> The worst I hoped is loosing the last save, but not everything.
> 
> Must I patch to a newer version ?
> I'm using a 2.4.3 version.

I would certainly upgrade to 2.4.7. There are know reiserfs trouble in 
2.4.3 - and 2.4.7 is a lot more stable than 2.4.3.

Rasmus

-- 
-- [ Rasmus 'Møffe' Bøg Hansen ] ---------------------------------------
Is there anything else I can contribute?
The latitude and longtitude of the bios writers current position, and
a ballistic missile.
                                                          -- Alan Cox
--------------------------------- [ moffe at amagerkollegiet dot dk ] --

Re: ReiserFS file corruption

[bvermeul]

On Mon, 6 Aug 2001, Emmanuel Varagnat wrote:

>
> Today, I crashed the kernel and after reboot the source file
> I was working on, was completly unreadable. The size indicated
> by 'ls' seems to be good but with bad data.
>
> Is this behavior normal (because the FS seems correct) ?
> The worst I hoped is loosing the last save, but not everything.

Yes, this is normal. You're being hit by metadata only journalling.
Configure your editor to make backup files, this will make sure you can
recover the last version.

Bas Vermeulen

-- 
"God, root, what is difference?"
	-- Pitr, User Friendly

"God is more forgiving."
	-- Dave Aronson

Re: ReiserFS file corruption

[Arjan van de Ven]

Emmanuel Varagnat wrote:
> 
> Today, I crashed the kernel and after reboot the source file
> I was working on, was completly unreadable. The size indicated
> by 'ls' seems to be good but with bad data.

Well reiserfs doesn't guarantee the CONTENTS of the file to be 
consistent after a crash; only the metadata.

Re: ReiserFS file corruption

[Troy Benjegerdes]

On Mon, Aug 06, 2001 at 01:14:02PM +0100, Arjan van de Ven wrote:
> Emmanuel Varagnat wrote:
> > 
> > Today, I crashed the kernel and after reboot the source file
> > I was working on, was completly unreadable. The size indicated
> > by 'ls' seems to be good but with bad data.
> 
> Well reiserfs doesn't guarantee the CONTENTS of the file to be 
> consistent after a crash; only the metadata.

Hrrrm, maybe the following change (or something like it) would be good 
for Documentation/Configure.help

===== Configure.help 1.46 vs edited =====
--- 1.46/Documentation/Configure.help   Sat Aug  4 11:40:39 2001
+++ edited/Configure.help       Tue Aug  7 13:27:41 2001
@@ -11706,7 +11706,12 @@
 CONFIG_REISERFS_FS
 
   Stores not just filenames but the files themselves in a balanced
-  tree.  Uses journaling.
+  tree.  Currently uses metatdata-only journaling.
+
+  (NOTE: metadata-only journalling only ensures the filesystem is
+  consistent after a crash, NOT the data! You need data AND metadata
+  journaling to guarantee open files do not get corrupted on a crash.
+  full data journalling is also slower.)
 
   Balanced trees are more efficient than traditional
   filesystem architectural foundations.

Re: ReiserFS file corruption

[Hans Reiser]

Emmanuel Varagnat wrote:
> 
> Today, I crashed the kernel and after reboot the source file
> I was working on, was completly unreadable. The size indicated
> by 'ls' seems to be good but with bad data.
> 
> Is this behavior normal (because the FS seems correct) ?
> The worst I hoped is loosing the last save, but not everything.
> 
> Must I patch to a newer version ?
> I'm using a 2.4.3 version.
> 
> Thanks
> 
> -Manu
> 
> PS: Finally I greped the partition and recover my file.
> -
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If your editor rewrites the entire file with every small change (and it probably
does), then if you crash at the wrong moment you can corrupt the entire file. 
If you use emacs or vi, it keeps a backup copy until the write is synced to disk
successfully.

You should definitely use 2.4.7, it is much better.

Hans