We kept getting this message on our forum. (like every 3-4 hours). We have 16 cores of CPU and 32GB of ram. I don’t think the resources is an issue. Oops The software powering this discussion forum encountered an unexpected problem. We apologize for the inconvenience. Detailed information about th…

I’d give postgres (db_shared_buffers) at least 16GB if not 20. But you need to make more DB connections. I can’t remember just how to do that. I think it’s max_connections in /etc/postgresql/postgresql.conf (inside the container that’s running postgres) that you need to change.

[image] Jay Pfaffman: But you need to make more DB connections I think so too. :+1: [image] Jay Pfaffman: I’d give postgres (db_shared_buffers) at least 16GB if not 20 Are you sure about that? That seems high. See PostgreSQL: Documentation: 13: 19.4. Resource Consumption If you have…

[image] Richard - Communiteq: Are you sure about that? That seems high. I always defer to you on matters like this, and I thought I was quoting advice you’d given in the past, so, NO I am not sure. :rofl: It’s pretty clear that the connections is the issue and increasing the RAM to 25% of 32…

[image] Jay Pfaffman: I thought I was quoting advice you’d given in the past I plead sort-of-guilty [image] How to scale further (2+MM posts, +80k per month) Ignore all the advice you find on the internet and set it to 40-50% of your memory. But that was then … :wink: [image] Jay P…

[image] jimmy0017: We set the following config in UNICORN_WORKERS: 32 UNICORN_SIDEKIQS: 2 Why? Those are the cause of you running out of connection slots.

I believe I saw somewhere saying UNICORN WORKER should be 2 * CPU. So i did the math to be 32. Should i scale down?

We tried to change the timeout setting for PSQL by running this ALTER ROLE discourse SET statement_timeout = '30000'; . And this query is the one got blocked, once every couple hours. [image] Not sure if you or anybody else has any idea on what happened?

[image] jimmy0017: I believe I saw somewhere saying UNICORN WORKER should be 2 * CPU. So i did the math to be 32. Should i scale down? No, please remove this and let the defaults values take place. This is the classic case of premature optimization.

[image] jimmy0017: We tried to change the timeout setting for PSQL by running this ALTER ROLE discourse SET statement_timeout = '30000'; . [image] jimmy0017: Not sure if you or anybody else has any idea on what happened? Yes, you touched stuff you shouldn’t touch :wink:

Discourse Crash due to PSQL connection issue

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Discourse Crash due to PSQL connection issue

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