Re: log messages for archive recovery progress

On Thu, Jan 12, 2012 at 10:04 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On Thu, Jan 12, 2012 at 2:13 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Wed, Jan 11, 2012 at 9:01 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>>> On Wed, Jan 11, 2012 at 1:54 PM, Satoshi Nagayasu <snaga(at)uptime(dot)jp> wrote:
>>>
>>>> However, I'm a bit afraid that it will confuse DBA if we use
>>>> "restored" under the pg_xlog replay context, because we have
>>>> already used "restored" that means a WAL file as successfully
>>>> "copied" (not "replayed") from archive directory into pg_xlog
>>>> directory under the archive recovery context.
>>>>
>>>> So, to determine the status of copying WAL files from
>>>> archive directory, I think we can use "restored", or
>>>> "could not restore" on failure.
>>>>
>>>> And to determine the status of replaying WAL files
>>>> in pg_xlog directory (even if a WAL is copied from archive),
>>>> we have to use "recover" or "replay".
>>>
>>> Agreed. I can change "restored" to "using", so we have two message types
>>>
>>> LOG:  restored log file "000000080000000000000047" from archive
>>> LOG:  using pre-existing log file "000000080000000000000047" from pg_xlog
>>
>> using seems pretty fuzzy to me.  replaying?
>
> That was my first thought, but the message relates to which file has
> been selected, and how. Once it has been selected it will be replayed.
> The idea is to have the two messages look similar.
>
> The original message was "restored log file..." and says nothing about
> replaying.
>
> We could change the old message (ugh! backwards compatibility alert)
>
>  LOG:  replaying log file "000000080000000000000047" after restore from archive
>  LOG:  replaying log file "000000080000000000000047" already in pg_xlog
>
> which doesn't sound much stronger to me... not sure.

Hmm, I don't know. But that phrasing does at least have the advantage
of being clearly parallel, which I like.

--
Robert Haas
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