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.

You need to collect some data so we know what is the bottleneck. Prometheus exporter plugin for Discourse

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 conversa…

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

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sam (Sam Saffron) February 23, 2021, 5:31am 14

This already happens, we have pretty aggressive caching direct in Redis for anon users on topic list pages and topic pages. 60s timeout.

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

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