Occasionally I get very high CPU load. Generally the operation is very smooth but then there are those burst of full CPU load. While that is happening, the forum give 502 errors or is VERY slow. I have a Hetzner server with 3 vCPUs and 4 GB of RAM. [Bildschirmfoto 2025-10-11 um 20.43.18] Anyone h…

This is what the console in the Hetzner backend shoes: [Bildschirmfoto 2025-10-11 um 20.43.06]

[image] GeorgSeifert: Anyone has an idea what could cause this? Can you run htop or similar on the server, to identify the process name which is causing the high CPU load?

A periodic process is running. Do you have swap? You’re running out of memory. I would add 2 to 4gb of swap.

I had to wait to catch an high CPU event. I ran htop and took some screenshots (I never used it so I don’t know what I’m looking at). [Bildschirmfoto 2025-10-13 um 20.42.31] [Bildschirmfoto 2025-10-13 um 20.43.30] [Bildschirmfoto 2025-10-13 um 20.43.55] [Bildschirmfoto 2025-10-13 um 20.43.02…

[image] pfaffman: Do you have swap? You’re running out of memory. I would add 2 to 4gb of swap. This is the first thing to do.

No swap is not a good look here, you are dangerously close to major issues.

@GeorgSeifert were you able to resolve your issue? If adding swap is the fix, please mark @pfaffman ’s post as the solution. It’s the button on the post menu that looks like a square with a checkmark in it.

I tried a different sever that has more RAM but slower CPU and is cheaper. I’ll monitor this for a few days.

Did you add swap? That is essential.

I thought double the physical RAM should do for now. The Discourse page says that a server with 1-2 MB RAM is enough to run it. So I thought I’m kind of save with 4 MB? Now it has 8. I’m not sure if our forum has a lot trafic (I just check the Reports and it says 15 logged in and 1000 not logged i…

Occasionally very high CPU load

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GeorgSeifert October 11, 2025, 6:56pm 2

This is what the console in the Hetzner backend shoes:

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CPU, Memory and Swap at 100% Self-hosting server-resources	7	664	December 8, 2021
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Forum Unusable due to "Can’t save in background: fork: Cannot allocate memory” Self-hosting	13	2480	October 5, 2020
Is 1GB RAM enough for both WordPress and Discourse? Self-hosting server-resources	22	4736	June 8, 2024
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Occasionally very high CPU load

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