We just had peak traffic of approx 1,500 concurrent (mostly anonymous) users visiting a single page. And the forum went into the mode, where the warning is displayed to all members concerning high load. CPU-Optimized Digital Ocean Droplet Dedicated CPU: 4 vCPUs RAM: 8 GB Unicorn workers: 10 Gi…

Yes, increasing unicorns is the first step here.

I have increased the workers to 24. No difference (goes still into “Due to extreme load, this is temporarily being shown to everyone as a logged-out user would see it.”), with a similar concurrent visitor peak (99% anonymous) just now: [image]

I know @sam has spent a lot of time on this recently and might have commentary?

@sam Any ideas on how to further optimize for peak traffic from anonymous traffic (e.g. if a singe topic goes viral on social media). In both cases outlined above, memory and CPU still have plenty of room (according to Digital Ocean), and we have not even hit a load of 4, still, the forum goes into …

[image] Just went into “extreme load mode” again, with only 600 concurrent visitors total (99% anonymous) and a load of not even 1.

I believe the DO data monitor is not sensitive enough and somewhat misleading. I experimented with extreme load with Hetzner and Digital ocean. With Hetzner when the extreme load message came up there was a short sharp peak where it would go to 120%. It lasted maybe a second, before dropping down…

We are going to need prometheus exporter reports to look any deeper. If you have the ram and the cpu … you can always add more unicorn workers, that will scale up for these peaks. You just don’t want to swap memory, cause performance will go way down.

[image] Terrapop: Any ideas on how to further optimize for peak traffic from anonymous traffic (e.g. if a singe topic goes viral on social media). Seems like in such a case that single topic page should be able to be cached and served statically for a short period without having to hit the ba…

That already happens dynamically under measured load on a per-topic basis, that’s exactly what [image] Terrapop: the forum went into the mode, where the warning is displayed to all members concerning high load. … is referring to. It’s READ ONLY though, so people can’t actually have conversat…

High load due to peak anonymous sessions, increase unicorn workers?

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Falco (Falco) February 21, 2021, 1:23am 7

You need to collect some data so we know what is the bottleneck.

Prometheus exporter plugin for Discourse

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High load due to peak anonymous sessions, increase unicorn workers?

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