competition

[Bron Gondwana]

On Wed, Sep 22, 2010 at 11:24:04PM +0200, Gabor Gombas wrote:
> On Wed, Sep 22, 2010 at 04:10:15PM +1000, Bron Gondwana wrote:
> 
> > Now - BDB database SHOULD be upgradable.  I want to find a BDB expert
> > to help me with that - (a) detecting that an upgrade is necessary, and
> > (b) doing the upgrade.
> 
> It was quite some time ago I last upgraded a Cyrus instance, but my
> upgrade script did the following:
> 
> - Run the _old_ version of db_recover. Just shutting down Cyrus is not
>   enough, without this step db_upgrade can fail.
> 
> - Run the _new_ version of db_upgrade.
> 
> - Run "db_checkpoint -1" to force the log to be rotated.
> 
> I think it won't be hard to implement steps 2 & 3 inside Cyrus, and I
> don't remember those steps taking a significant amount of time, but I
> don't know how it would be possible to implement step 1. However if the
> BDB version change does not bring a change to the on-disk DB log format,
> then it may be possible to skip steps 1 & 3.

Ok - so the upshot is that we need to implement a "shutdown" path, either
in master.c or in ctl_cyrusdb - and we need to make sure it gets run
during the usual shutdown path.

Bron.