Re: BUG #11603: replication, pg_basebackup and high load

On 2014-10-08 13:19:27 +0000, mdglange@gmail.com wrote:
> The test I did involved the following: a master database with two slaves. On
> the master two replication slots have been configured as per the
> documentation. One slave active before I put some "heavy" load (the
> environment is scaled such, that inserting a few gigabytes of insert
> statements is a heavy load. This is on purpose)

Replication slots currently only reserve resources after they've been
used the first time. I.e. when you create a physical replication slot it
doesn't immediately reserve resources - a client needs to connect to it
once, telling it from where on to reserve resources.

You can see the slot's reserved resources in the pg_replication_slots
view.

So, what you could do is to connect to the slots once, for a short time,
using pg_receivexlog --slots. Or just use the -X stream method for
pg_basebackup.

Greetings,

Andres Freund

--
 Andres Freund                       http://www.2ndQuadrant.com/
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