Re: BUG #17974: Walsenders memory usage suddenly spike to 80G+ causing OOM and server reboot

On Thu, Jun 15, 2023 at 10:02 AM Michael Paquier <michael@paquier.xyz> wrote:
>
> On Wed, Jun 14, 2023 at 08:04:53PM -0400, Michael Guissine wrote:
> > On Wed, Jun 14, 2023 at 6:15 PM Andres Freund <andres@anarazel.de> wrote:
> >>>> Any known issues in pg 14.8 that would trigger this behaviour?
> >>>
> >>> Yes, there are known issues with memory handling in logical
> >>> replication setups.  See for example this thread:
> >>>
> >>> https://www.postgresql.org/message-id/CAMnUB3oYugXCBLSkih+qNsWQPciEwos6g_AMbnz_peNoxfHwyw@mail.gmail.com
> >>
> >> Why would 14.8 have made that problem worse?
>
> Hmm?  I don't necessarily imply that 14.8 made it worse, but that
> there are known issues in this area as the other thread mention (which
> is mainly about v15, actually, where the situation could be a bit
> better).

Yeah, IIUC the logical decoding could use nearly unlimited memory
depending on workloads (see analysis here[1]).

Regards,

[1]
https://www.postgresql.org/message-id/OS3PR01MB6275CAC41E8564D60DC66D229E769%40OS3PR01MB6275.jpnprd01.prod.outlook.com

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com