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

On Wed, Mar 23, 2011 at 12:44 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Robert Haas <robertmhaas(at)gmail(dot)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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