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Replacing a $3000/mo Heroku bill with a $55/mo server

(disco.cloud)
804 points jryio | 5 comments | 21 Oct 25 20:28 UTC | HN request time: 0s | source
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speedgoose ◴[21 Oct 25 21:12 UTC] No.45661785[source]▶
Looking at the htop screenshot, I notice the lack of swap. You may want to enable earlyoom, so your whole server doesn't go down when a service goes bananas. The Linux Kernel OOM killer is often a bit too late to trigger.

You can also enable zram to compress ram, so you can over-provision like the pros'. A lot of long-running software leaks memory that compresses pretty well.

Here is how I do it on my Hetzner bare-metal servers using Ansible: https://gist.github.com/fungiboletus/794a265cc186e79cd5eb2fe... It also works on VMs.

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TheDong ◴[22 Oct 25 03:05 UTC] No.45664508[source]▶
Even better than earlyoom is systemd-oomd[0] or oomd[1].

systemd-oomd and oomd use the kernel's PSI[2] information which makes them more efficient and responsive, while earlyoom is just polling.

earlyoom keeps getting suggested, even though we have PSI now, just because people are used to using it and recommending it from back before the kernel had cgroups v2.

[0]: https://www.freedesktop.org/software/systemd/man/latest/syst...

[1]: https://github.com/facebookincubator/oomd

[2]: https://docs.kernel.org/accounting/psi.html

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1. geokon ◴[22 Oct 25 08:59 UTC] No.45666462[source]▶
Do you have any insight in to why this isn't included by default in distros like Ubuntu. It's kind of bewildering that the default behavior on Ubuntu is to just lock up the whole system on OOM
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2. TheDong ◴[22 Oct 25 09:42 UTC] No.45666764[source]▶
systemd-oomd I'm pretty sure is enabled by default in fedora and ubuntu desktop.

I think it's off on the server variants.

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3. galangalalgol ◴[22 Oct 25 10:17 UTC] No.45667002[source]▶
Is there any way to get something like the oomd or zram that works on gpu memory? I run into gpu memory leaks more often. Itbseems to be electron usually.
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4. geokon ◴[22 Oct 25 10:53 UTC] No.45667257[source]▶
Kubuntu LTS definitely didnt have it by default. And there are no system settings exposing it (or ZRAM)
5. fireant ◴[23 Oct 25 03:50 UTC] No.45677987{3}[source]▶
GPU memory model quite different from CPU memory model, with application level explicit synchronization and coherency and so on. I don't think that transparent compression would be possible, and even if it would surely carry drastic perf downside