Re: Warm standby can't start because logs stream too quickly from the master

On Sat, Dec 2, 2017 at 11:02 AM, Zach Walton  wrote:

> Looking at the startup process:
>
> postgres 16749  4.1  6.7 17855104 8914544 ?    Ss   18:36   0:44 postgres:
> startup process   recovering 0000000800005B1C00000030
>
> Then a few seconds later:
>
> postgres 16749  4.2  7.0 17855104 9294172 ?    Ss   18:36   0:47 postgres:
> startup process   recovering 0000000800005B1C00000047
>
> It's replaying logs from the master, but it's always a few behind, so
> startup never finishes. Here's a demonstration:
>
> # while :; do echo $(ls data/pg_xlog/ | grep -n $(ps aux | egrep "startup
> process" | awk '{print $15}')) $(ls data/pg_xlog/ | wc -l); sleep 1; done
> # current replay location                     # number of WALs in pg_xlog
> 1655:0000000800005B1C00000064 1659
> 1656:0000000800005B1C00000065 1660
> 1658:0000000800005B1C00000067 1661
> 1659:0000000800005B1C00000068 1662
> 1660:0000000800005B1C00000069 1663
>
> Generally this works itself out if I wait (sometimes a really long time).
> Is there a configuration option that allows a warm standby to start without
> having fully replayed the logs from the master?
>


Warm standbys aren't supposed to start up, that is what makes them warm.
Are you trying to set up a hot standby?  Are you trying to promote a warm
standby to be the new master (but usually you would do that when the
current master has died, and so would no longer be generating log.)

Cheers,

Jeff