Re: locks within select - Mailing list pgsql-general

From Laurenz Albe
Subject Re: locks within select
Date
Msg-id 86b7e09ff47c45f4455bc1421878ff33d505049c.camel@cybertec.at
Whole thread Raw
In response to Re: locks within select  (Marc Millas <marc.millas@mokadb.com>)
Responses Re: locks within select
List pgsql-general
On Tue, 2021-12-14 at 13:38 +0100, Marc Millas wrote:
> but... when you do setup a streaming replication, there is, in postgresql.conf, a variable: 
> max_standby_streaming_delay = 30s # max delay before canceling queries when reading streaming WAL;
> 
> as the secondary is, by nature, read only, I was wondering why it can be necessary to cancel a read request...

Perhaps this can explain some of what is going on:

https://www.cybertec-postgresql.com/en/streaming-replication-conflicts-in-postgresql/

Yours,
Laurenz Albe
-- 
Cybertec | https://www.cybertec-postgresql.com




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