Re: Clean shutdown and warm standby - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: Clean shutdown and warm standby
Date
Msg-id 4A1EA775.3090705@enterprisedb.com
Whole thread Raw
In response to Re: Clean shutdown and warm standby  (Simon Riggs <simon@2ndQuadrant.com>)
Responses Re: Clean shutdown and warm standby  (Guillaume Smet <guillaume.smet@gmail.com>)
Re: Clean shutdown and warm standby  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers
Simon Riggs wrote:
> On Thu, 2009-05-28 at 17:21 +0300, Heikki Linnakangas wrote:
>> Simon Riggs wrote:
>>> I don't think it does, please look again. 
>> Still looks ok to me. pgarch_ArchiverCopyLoop() loops until all ready 
>> WAL segments have been archived (assuming no errors).
> 
> No, it doesn't now, though it did used to. line 440.

postmaster never sends SIGTERM to pgarch, and postmaster is still alive.

>>>> Ok, we're good then I guess.
>>> No, because as I said, if archive_command has been returning non-zero
>>> then the archive will be incomplete.
>> Yes. You think that's wrong? How would you like it to behave, then? I 
>> don't think you want the shutdown to wait indefinitely until all files 
>> have been archived if there's an error.
> 
> The complaint was that we needed to run a manual step to synchronise the
> pg_xlog directory on the standby. We still need to do that, even after
> the patch has been committed because 2 cases are not covered, so what is
> the point of the recent change? It isn't enough. It *might* be enough,
> most of the time, but you have no way of knowing that is the case and it
> is dangerous not to check.

So you check. This solves Guillaume's immediate concern. If you have a 
suggestion for further improvements, I'm all ears.

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


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