Re: Reducing walreceiver latency with a latch

On 13 September 2010 12:47, Thom Brown <thom(at)linux(dot)com> wrote:
> On 13 September 2010 12:40, Heikki Linnakangas
> <heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
>> Now that we have the wonderful latch facility, let's use it to reduce the
>> delay between receiving a piece of WAL and applying in the standby.
>> Currently, the startup process polls every 100ms to see if new WAL has
>> arrived, which adds an average a 50 ms delay between a transaction commit in
>> the master and it appearing as committed in a hot standby server. The latch
>> patch eliminated a similar polling delay in walsender already, the attached
>> patch does the same for walreceiver.
>>
>> After this patch, there is no unnecessary delays in the streaming
>> replication code path. Note that this is all still asynchronous, just with
>> reduced latency.
>>
>> This is pretty straightforward, but any comments?
>
> Is that supposed to be waiting 5000ms?

Ignore me, I can see that it's right.

--
Thom Brown
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