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

(disco.cloud)
804 points jryio | 13 comments | 21 Oct 25 20:28 UTC | HN request time: 0.593s | source | bottom
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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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awesome_dude ◴[21 Oct 25 22:38 UTC] No.45662628[source]▶
How do you get swap on a VPS?
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justsomehnguy ◴[21 Oct 25 23:32 UTC] No.45663111[source]▶
Search "linux enable swap in a file"

    To enable a swap file in Linux, first create the swap file using a command like sudo dd if=/dev/zero of=/swapfile bs=1G count=1 for a 1GB file. Then, set it up with sudo mkswap /swapfile and activate it using sudo swapon /swapfile. To make it permanent, add /swapfile swap swap defaults 0 0 to your /etc/fstab file.
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1. awesome_dude ◴[21 Oct 25 23:33 UTC] No.45663117[source]▶
Strongly suggest you try doing that on a VPS, then report back
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2. ahepp ◴[21 Oct 25 23:44 UTC] No.45663205[source]▶
What do you think is going to happen? I tested it out on an ec2 instance just now and it seems to have worked as one would expect.
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3. justsomehnguy ◴[21 Oct 25 23:51 UTC] No.45663268[source]▶
https://news.ycombinator.com/item?id=45007821

And that was like... two years ago? 1GB of RAM and actually ~700MB usable before I found the proper magik incantations to really disable kdump.

Also have used 1GB machines for literally years.

Strongly suggest you shouldn't strongly suggest.

replies(1): >>45663625 #
4. awesome_dude ◴[22 Oct 25 00:35 UTC] No.45663613[source]▶
EC2 != VPS
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5. awesome_dude ◴[22 Oct 25 00:37 UTC] No.45663625[source]▶
Uh.. your link... doesn't show how a VPS can have SWAP enabled

You do understand what's being discussed... right?

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6. justsomehnguy ◴[22 Oct 25 00:53 UTC] No.45663739{3}[source]▶
Literally up the chain: https://news.ycombinator.com/item?id=45663111

Or you have a very peculiar understanding what 'VPS' means.

replies(1): >>45664617 #
7. awesome_dude ◴[22 Oct 25 03:24 UTC] No.45664617{4}[source]▶
https://en.wikipedia.org/wiki/Virtual_private_server

As I said earlier

https://news.ycombinator.com/threads?id=awesome_dude#4566311...

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8. cmpxchg8b ◴[22 Oct 25 05:28 UTC] No.45665189{3}[source]▶
They both offer virtualized guests under a hypervisor host. EC2 does have more offload specialization hardware but for the most part they are functionally equivalent, unless I'm missing something...
9. Zekio ◴[22 Oct 25 08:57 UTC] No.45666456[source]▶
well once you "need" that swap, it will be writing pages across the network due to the storage being external to the physical server, so the latency is terrible
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10. kassner ◴[22 Oct 25 09:38 UTC] No.45666737{3}[source]▶
Put swap on the “instance store” disk, not EBS.
11. justsomehnguy ◴[22 Oct 25 19:52 UTC] No.45674279{5}[source]▶
Hello, it's the year 2025 here. If you use OpenVZ-like ancient shit - it's on you.

So no, VPS is a proper virtualization for a 15 years. And with a proper virtualization you have the full control.

12. ahepp ◴[23 Oct 25 02:19 UTC] No.45677456{3}[source]▶
Latency of swap is always terrible in comparison to RAM. RAM vs disk is already something ~1000x right? I've never characterized EBS vs trad ssd, but I would be surprised if it's more than 10x.

I don't think using swap as "emergency RAM" makes a lot of sense in 2025. The arguments in favor of swap which I find convincing are about allowing the system to evict low use pages which otherwise would not be evictable.

13. ahepp ◴[23 Oct 25 02:22 UTC] No.45677481{3}[source]▶
What VPS do you think this would cause problems on? Why?