Re: New trigger option of pg_standby

Fujii Masao wrote:
> Hi,
> 
> On Tue, Apr 14, 2009 at 2:41 PM, Fujii Masao <masao.fujii@gmail.com> wrote:
>> I'd like to propose another simple idea; pg_standby deletes the
>> trigger file *whenever* the nextWALfile is a timeline history file.
>> A timeline history file is restored at the end of recovery, so it's
>> guaranteed that the trigger file is deleted whether nextWALfile
>> exists or not.
>>
>> A timeline history file is restored also at the beginning of
>> recovery, so the accidentally remaining trigger file is deleted
>> in early warm-standby as a side-effect of this idea.
> 
> Here is the revised patch as above.
> 
> If you notice something, please feel free to comment.

Ok, looking at this in more detail now. A couple of small things:

We mustn't remove the trigger file immediately even in fast mode. As 
noted elsewhere in this thread, we have the same bug in fast mode where 
pg_standby gets stuck if you copy WAL files directly into pg_xlog.

pg_standby should exit with code 0 only if the file is restore 
successfully. As the patch stands it also returns 0 when smart failover 
is done.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com