Re: [DISCUSSION] Journal playback

[Vladimir Serbinenko <phcoder@gmail.com>]

Marco Gerards wrote:

>Vladimir Serbinenko <phcoder@gmail.com> writes:
>
>  
>
>>I've seen that journal playback is one of TODO items. I think it's bad
>>idea because:
>>
>>1) It'll increase the size of FS modules. And fs modules are often embed
>>in core image. So their size is critical
>>    
>>
>
>The size of a filesystem module is now about 4KB.  We do not know yet
>how much the size will increase when journaling is possible.
>
>  
>
>>2) It'll decrease safety because now GRUB doesn't write to FS and then
>>it'll be so the GRUB's bugs could damage FS.
>>3) It'll be impossible to use resume/resume2 because the fs environment
>>is not more the same as at the hibernation.
>>    
>>
>
>The data should not be written to the filesystem.  Instead the
>journal should be played back for the data that is read.  I am not yet
>sure if it is possible, easy and fast enough.  But I do think it is
>worthwhile to consider journaling support.
>
>  
>
It'll give for sure considerable amount of work but the question if
it'll give real advantages?
Journaling was made to keep *FS* from the corruption. *Not* the data. So
even if data needed
by GRUB is corrupted (that is not very probable because kernels, initrds
and GRUB data)
there is a high probability that journaling will simply remove this
corrupted data. On the other
hand it can perhaps create strange bugs and make maintnaining harde
                                                                     
Vladimir