[rsyslog] Development of failsafe disk based queue

[Rainer Gerhards]

On Wed, 2008-10-01 at 13:15 +0200, David Ecker wrote:
> Rainer Gerhards schrieb:
> > One thing I forgot to mention: a pure disk queue (not a disk-assisted
> > one) gets you as close to your goal as possible (well, mostly - we
> > could, at a considerable performance expense, require synced writing).
> > With that case, all data is immediately stored on disk. You can
> > configure it to also write the meta data out immediately (and again with
> > sync, not yet supported). However, you still have a window of exposure,
> > for example if the power loss happens right in the middle of when the
> > disk actually writes data to the disk sector.
> >
> >   
> If that would work it would be perfect. For testing I could actually
> pass the correct fctl flag inside of queue.c hardcoded if that is all
> that is needed.

that works ;) You just need to fine-tune the queue params. If you find
problems with that, I am more than happy to help.

> > I still wonder why this scenario would be useful to address...

very interesting scenario. Never thought about such one :) If you need
to enhance the queue (for block devices), I can provide a some hints.
But, given the other priorities which are required by a much broader
user base, involving me more than a hint here or there would probably
require a consulting contract. Sorry for being so bluntly, but I think
it is always good to set the right expectation level.

Rainer