Re: Journaling: Surviving or allowing unclean shutdown?

Chris Mason
2001-01-06T20:35:45Z

On Saturday, January 06, 2001 09:09:51 PM +0100 Stefan Traby
<stefan@hello-penguin.com> wrote:

> On Sat, Jan 06, 2001 at 08:57:26PM +0100, Marc Lehmann wrote:
>
>> reply. Sure, you can do virtual log replays, but for example the reiserfs
>> log is currently 32mb. Pinning down that much memory for a virtual log
>> reply is not possible on low-memory machines.
>
> Nobody with working brain would read it completely into memory.
> One just put the block-# that are in the journal into a hash-table
> and read the block out of the journal when it's requested.
> Because there may be multiple copies of the same block in the
> journal, one should take the newest one that can be found in
> the last commited transaction.
>
> IMHO Chris Mason already wrote such code, at least he talked about
> it...
>
Talked about it, but never wrote it. However, I know there was code to do
this for grub, I'm not sure if it ever made it into their releases.

-chris