[lug] Rather disturbing

[Gary Hodges]

Zan Lynx wrote:

>On Thu, 2004-02-26 at 15:41, Gary Hodges wrote:
>  
>
>>1.  All my opera bookmarks and settings look to be the default values.  
>>Actually, now that I'm looking again, there are no bookmarks at all.
>>
>>2.  I ran tin to check some news and the listed newsgroups I subscribe 
>>to had changed to partial lines of data from a data file I recognize. 
>>
>>SuSE 9.0 w/ReiserFS
>>
>>    
>>
>Reiser version 3 journals meta-data but not data.  There are patches
>(which may be in SuSE 9, I don't know) to make Reiser journal in ordered
>mode (write the data FIRST and then update meta-data), or even full data
>journaling (very slow).
>
>The meta-data only journalling means that your directories, file types
>and names and permissions, things like that will be fine, but the actual
>contents of files that were being modified during the crash may be
>indeterminate.
>
>What probably happened is that your bookmark file was being updated and
>the filesystem had allocated some new blocks to it, but hadn't actually
>written anything into those new blocks yet.  So, those new blocks
>contained data from another older file.
>
>This is pretty common for meta-data journaling filesystems.  XFS does it
>too, although it tends to create files full of zeros instead of random
>data.
>  
>

Thanks for the comments.  Sure sounds like what you describe is exactly 
what happened.  Would ext3 have done the same thing?  I also discovered 
that a file I was editing at the time, and had been saved, has 
disappeared.  This seems to contradict slightly your description of how 
ReiserFS works.  I don't know about the availability of patches for 
ReiserFS for SuSE 9.0.  I certainly haven't applied any knowingly, but I 
will look into this.

On the bright side, my backups seem to be all there and in good working 
order up through my daily backup that was done last night.

Cheers,
Gary