Re: Ticket 128: Hot Standby and Streaming Replication

Le 13/02/2010 23:32, Magnus Hagander a écrit :
> 2010/2/10 Guillaume Lelarge <guillaume(at)lelarge(dot)info>:
>> Le 03/02/2010 22:00, Guillaume Lelarge a écrit :
>>> Le 03/02/2010 21:26, Magnus Hagander a écrit :
>>>> On Wed, Feb 3, 2010 at 21:22, Guillaume Lelarge <guillaume(at)lelarge(dot)info> wrote:
>>>>> Le 03/02/2010 21:04, Magnus Hagander a écrit :
>>>>>> On Wed, Feb 3, 2010 at 00:11, Guillaume Lelarge <guillaume(at)lelarge(dot)info> wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> I tried both of them yesterday night and tonight to have a look at what
>>>>>>> could be done on pgAdmin for these features. AFAICT, not a lot.
>>>>>>>
>>>>>>> Actually, I have a really small patch that adds some informations in the
>>>>>>> server panel. This information is quite simple. It tells the user if the
>>>>>>> selected server is in recovery mode and the last xlog replay location.
>>>>>>> I'm not sure we can do more. Streaming Replication can be detected if
>>>>>>> max_wal_senders is greater than zero, but I'm not sure we really need to
>>>>>>> add this kind of information on the server panel.
>>>>>>
>>>>>> It would be interesting to know *which* slaves are connected to a master, no?
>>>>>>
>>>>>
>>>>> AFAICT, there is no way to know that automatically in Hot Standby and in
>>>>> Streaming Replication. If you know some way to get that, I'm really
>>>>> interested. At first, I had hoped I could at least get the conninfo
>>>>> string on the slave, but recovery parameters are not available via show.
>>>>
>>>> Hmm. In that case, a way to do it should perhaps be created :-)
>>>>
>>>
>>> This means working on patch for the Streaming Replication. Could be
>>> interesting, but not something I can do right now.
>>>
>>
>> This new version of the patch adds support for
>> pg_last_xlog_receive_location().
>>
>> During FOSDEM, I discussed with Heikki about some interesting (at least
>> for us) informations: mainly knowing who the master is and knowing who
>> the slaves are.
>>
>> He confirmed me there is actually no way to get that information.
>> There's also no way to have the contents of recovery.conf available as
>> all other GUCs. We found that we could at least read the recovery.conf
>> file in the master with pg_file_read, which will give us the master host
>> (via the primary_conninfo parameter) for people using the adminpack
>> module contrib. Is it something interesting enough that I put some time
>> to code this? or do we stop here, commit what I already have and see
>> later what's coming next? (the "what's coming next" could be something I
>> would code for next release)
>
> Parsing primary_conninfo certainly seems *really* ugly. I think we put
> in what you have so far, and then lobby Heikki to get better functions
> already in 9.0 :-)
>

Commited.

--
Guillaume.
http://www.postgresqlfr.org
http://dalibo.com