Re: Update of replication/README

On Wed, Mar 9, 2011 at 9:01 PM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
> On Thu, Mar 10, 2011 at 2:00 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> On Wed, Mar 9, 2011 at 6:11 AM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
>>> The attached patch updates replication/README to reflect current
>>> walsender/walreceiver behavior. It doesn't include any description
>>> about sync rep. That would need to be added later.
>>
>> Hrm.  What about this hunk?
>>
>> -Each walsender allocates an entry from the WalSndCtl array, and advertises
>> -there how far it has streamed WAL already. This is used at checkpoints, to
>> -avoid recycling WAL that hasn't been streamed to a slave yet. However,
>> -that doesn't stop such WAL from being recycled when the connection is not
>> -established.
>> +Each walsender allocates an entry from the WalSndCtl array, and tracks
>> +information about replication progress. User can monitor them via
>> +statistics views.
>>
>> Is the deleted text not (or no longer) true?
>
> Yes. But, in fact, the deleted text is false in not only 9.1dev but
> also 9.0. IIRC,
> though my original patch of streaming replication prevented checkpoint from
> recycling unsent WAL files, that behavior was cut out and we introduced
> wal_keep_segments parameter before release of 9.0. But unfortunately I had
> not noticed that text until I read README yesterday...

OK, committed.

--
Robert Haas
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