Date: Thu, 14 Jan 2016 18:14:21 +0100
From: Andres Freund <andres@anarazel.de>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
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Subject: Re: Performance degradation in commit ac1d794
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On 2016-01-14 12:07:23 -0500, Robert Haas wrote:
> > Do we want to provide a backward compatible API for all this? I'm fine
> > either way.
>
> How would that work?

I'm thinking of something like;

int WaitOnLatchSet(LatchEventSet *set, int wakeEvents, long timeout);

int
WaitLatchOrSocket(volatile Latch *latch, int wakeEvents, pgsocket sock,long timeout)
{
        LatchEventSet set;

        LatchEventSetInit(&set, latch);

        if (sock != PGINVALID_SOCKET)
           LatchEventSetAddSock(&set, sock);

        return WaitOnLatchSet(set, wakeEvents, timeout);
}

I think we'll need to continue having wakeEvents and timeout parameters
for WaitOnLatchSet, we quite frequently want to wait socket
readability/writability, not wait on the socket, or have/not have
timeouts.


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