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

(disco.cloud)
804 points jryio | 1 comments | 21 Oct 25 20:28 UTC | HN request time: 0.207s | 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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1. cmurf ◴[22 Oct 25 05:09 UTC] No.45665086[source]▶
Some workloads may do better with zswap. Cache is compressed, and pages evicted to disk based swap on an LRU basis.

The case of swap thrashing sounds like a misbehaving program, which can maybe be tamed by oomd.

System responsiveness though needs a complete resource control regime in place, that preserves minimum resources for certain critical processes. This is done with cgroupsv2. By establishing minimum resources, the kernel will limit resources for other processes. Sure, they will suffer. That’s the idea.