Re: making write location work (was: Efficient transaction-controlled synchronous replication)

Robert Haas <robertmhaas@gmail.com>

From: Robert Haas <robertmhaas@gmail.com>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: Simon Riggs <simon@2ndquadrant.com>, Fujii Masao <masao.fujii@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2011-03-23T18:25:51Z

Lists: pgsql-hackers

On Wed, Mar 23, 2011 at 12:44 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> Specifically, if we're not going to remove write location, then I
>> think we need to apply something like the attached.
>
>>                       while (walrcv_receive(0, &type, &buf, &len))
>>                               XLogWalRcvProcessMsg(type, buf, len);
>
>> +                     /* Let the master know that we received some data. */
>> +                     XLogWalRcvSendReply();
>
> What if we didn't actually receive any new data?

The portion of the code immediately preceding what's included in the
diff guards against that, and there is a second guard in
XLogWalRcvSendReply().

-- 
Robert Haas
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