Re: Logical Replication WIP

On 12/11/16 20:19, Andres Freund wrote:
> On 2016-11-10 23:31:27 +0100, Petr Jelinek wrote:
>> On 04/11/16 13:15, Andres Freund wrote:
>>>
>>>  /* Prototypes for private functions */
>>> -static bool libpq_select(int timeout_ms);
>>> +static bool libpq_select(PGconn *streamConn,
>>> +                         int timeout_ms);
>>>
>>> If we're starting to use this more widely, we really should just a latch
>>> instead of the plain select(). In fact, I think it's more or less a bug
>>> that we don't (select is only interruptible by signals on a subset of
>>> our platforms).  That shouldn't bother this patch, but...
>>>
>>>
>>
>> Agree that this is problem, especially for the subscription creation
>> later. We should be doing WaitLatchOrSocket, but the question is which
>> latch. We can't use MyProc one as that's not the latch that WalReceiver
>> uses so I guess we would have to send latch as parameter to any caller
>> of this which is not very pretty from api perspective but I don't have
>> better idea here.
> 
> I think we should simply make walsender use the standard proc
> latch. Afaics that should be fairly trivial?

Walreceiver you mean. Yeah that should be simple, looking at the code I
am not quite sure why it uses separate latch in the first place.

--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
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