Re: Performance degradation in commit ac1d794

On Thu, Jan 14, 2016 at 12:06 PM, Andres Freund <andres@anarazel.de> wrote:
> On 2016-01-14 11:31:03 -0500, Robert Haas wrote:
>> On Thu, Jan 14, 2016 at 10:56 AM, Andres Freund <andres@anarazel.de> wrote:
>> I think your idea of a data structure the encapsulates a set of events
>> for which to wait is probably a good one.  WaitLatch doesn't seem like
>> a great name.  Maybe WaitEventSet, and then we can have
>> WaitLatch(&latch) and WaitEvents(&eventset).
>
> Hm, I'd like to have latch in the name. It seems far from improbably to
> have another wait data structure. LatchEventSet maybe? The wait would be
> implied by WaitLatch.

I can live with that.

> So effectively we'd create a LatchEventSet feLatchSet; somewhere global
> (and update it from a backend local to the proc latch in
> SwitchToSharedLatch/SwitchBackToLocalLatch()). Then change all WaitLatch
> calls to refer to those.

Sure.

> Do we want to provide a backward compatible API for all this? I'm fine
> either way.

How would that work?

-- 
Robert Haas
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