Re: logical replication - still unstable after all these months

On 2017-05-26 08:10, Erik Rijkers wrote:

> If you run a pgbench session of 1 minute over a logical replication
> connection and repeat that 100x this is what you get:
>
> At clients 90, 64, 8, scale 25:
> -- out_20170525_0944.txt
> 100 -- pgbench -c 90 -j 8 -T 60 -P 12 -n -- scale 25
> 7 -- Not good.
> -- out_20170525_1426.txt
> 100 -- pgbench -c 64 -j 8 -T 60 -P 12 -n -- scale 25
> 18 -- Not good.
> -- out_20170525_2049.txt
> 100 -- pgbench -c 8 -j 8 -T 60 -P 12 -n -- scale 25
> 10 -- Not good.
> At clients 90, 64, 8, scale 5:
> -- out_20170526_0126.txt
> 100 -- pgbench -c 90 -j 8 -T 60 -P 12 -n -- scale 5
> 2 -- Not good.
> -- out_20170526_0352.txt
> 100 -- pgbench -c 64 -j 8 -T 60 -P 12 -n -- scale 5
> 3 -- Not good.
> -- out_20170526_0621.txt
> 100 -- pgbench -c 8 -j 8 -T 60 -P 12 -n -- scale 5
> 4 -- Not good.

It seems this problem is a bit less serious than it did look to me (as
others find lower numbers of fail).

Still, how is its seriousness graded by now? Is it a show-stopper?
Should it go onto the Open Items page?

Is anyone still looking into it?

thanks,

Erik Rijkers

> The above installations (master+replica) are with Petr Jelinek's (and
> Michael Paquier's) last patches
> 0001-Fix-signal-handling-in-logical-workers.patch
> 0002-Make-tablesync-worker-exit-when-apply-dies-while-it-.patch
> 0003-Receive-invalidation-messages-correctly-in-tablesync.patch
> Remove-the-SKIP-REFRESH-syntax-suggar-in-ALTER-SUBSC-v2.patch