Re: [HACKERS] logical replication - still unstable after all thesemonths

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