It looks like 2+2 may not be enough any more… I’m managing a fairly unassuming (no big/fancy plugins, etc) Discourse instance that, as of today, is failing to bootstrap because ember is chewing all the RAM it can find, and all the swap, and grinding the machine into unresponsiveness. Adding another…

Overcommit is irrelevant here, because the problem isn’t processes being OOM-killed prematurely, it’s just trying to stuff ten pounds of allocated memory into a five pound sack. It’s not practically possible to run a Discourse rebuild with overcommit_memory=2, because ember (amongst other things, n…

I’m not sure I entirely agree with your analysis! As I understand it, overcommit allows processes to allocate memory which they don’t touch. It’s not just about OOM-killer behaviour. But as I say, I’d like to run some controlled experiments, that’s a better way to see what does and doesn’t make a …

I have 4GB of RAM and many plugins (no swap file of what I am aware of). How many plugins do you have and do you think plain 4GB of RAM is enough?

[image] Ed_S: As I understand it, overcommit allows processes to allocate memory which they don’t touch. Partially correct, but even so, it’s irrelevant, because the problem being discussed in this topic is processes allocating memory which they do touch, and touching more of it than the syst…

Can you confirm that post @david ’s changes memory requirements are down? We should be in a reasonable state now. The next big jump is going to be pre-compiling and distributed pre-compiled assets, it is a pretty big change to get there but it will erase a big bunch of work from the Internet once do…

[image] mpalmer: the problem being discussed in this topic is processes allocating memory which they do touch With respect, I’m not sure about that. I’ve seen log files showing failures in forking. We’re saying in this thread that it’s “memory requirements” but that does - in my view - includ…

That was a fresh build without any plugins. I can try another one with a few plugins enabled and maybe temporarily disable swap to confirm that the build goes through (it’ll probably take a few days until I have time, though).

Ok, next test completed. I built with the following plugins: https://github.com/discourse/docker_manager.git https://github.com/discourse/discourse-data-explorer https://github.com/communiteq/discourse-legal-compliance https://github.com/pfaffman/discourse-allow-pm-to-staff https://github.com/sing…

On my way the problem is swap file, after increasing from 0 to 2GB, everything is okay for now. sudo fallocate -l 2G /swapfile sudo chmod 600 /swapfile sudo mkswap /swapfile sudo swapon /swapfile echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab in the your server terminal. After …

I’m hitting a big increase in memory needed to rebuild. I have 8GB memory and even adding an 8GB swapfile it runs out of space on this step: cd /var/www/discourse && sudo -E -u discourse bundle exec rake multisite:migrate It’s a multisite install with four forums. I haven’t had to add a swapfile be…

High rebuild memory requirements: April 2025 edition

Support Self-hosting

NateDhaliwal (Nate Dhaliwal) February 15, 2026, 8:35am 31

See:

Topic		Replies	Views
Precompiling assets takes 20 minutes Self-hosting server-resources	18	1490	January 31, 2024
Failed to upgrade discourse instance to Feb 15 2022 Self-hosting server-resources	29	2964	February 16, 2022
Suddenly boot strapping is failing Self-hosting two-container	25	1159	December 30, 2022
Upgrade from 3.2.0.beta3-dev to 3.2.0.beta3 failed due to out of memory Self-hosting server-resources	18	1607	February 6, 2024
Failed to bootstrap due to out of memory killer Bug	35	2651	April 29, 2021

High rebuild memory requirements: April 2025 edition

Related topics