Re: MultiXact\SLRU buffers configuration

> 10 нояб. 2020 г., в 23:07, Tomas Vondra <tomas.vondra@enterprisedb.com> написал(а):
>
> On 11/10/20 7:16 AM, Andrey Borodin wrote:
>>
>>
>> but this picture was not stable.
>>
>
> Seems we haven't made much progress in reproducing the issue :-( I guess
> we'll need to know more about the machine where this happens. Is there
> anything special about the hardware/config? Are you monitoring size of
> the pg_multixact directory?

It's Ubuntu 18.04.4 LTS, Intel Xeon E5-2660 v4, 56 CPU cores with 256Gb of RAM.
PostgreSQL 10.14, compiled by gcc 7.5.0, 64-bit

No, unfortunately we do not have signals for SLRU sizes.
3.5Tb mdadm raid10 over 28 SSD drives, 82% full.

First incident triggering investigation was on 2020-04-19, at that time cluster was running on PG 10.11. But I think it
washappening before. 

I'd say nothing special...

>
>> How do you collect wait events for aggregation? just insert into some table with cron?
>>
>
> No, I have a simple shell script (attached) sampling data from
> pg_stat_activity regularly. Then I load it into a table and aggregate to
> get a summary.

Thanks!

Best regards, Andrey Borodin.