Hi,

Do you have suggestions for kernel tweaks for getting the most out of a RAM limited system?

I am running a service requiring 2GB of RAM (netbird) on a VPS which has just 1 GB of memory. I am doing so because I am a stingy bastard and I use only free VPSs for my personal use so I get what I am paying for.

Because of this hardware limit in about 12 hours from service start I begin swapping a bit too much. This would still be manageable but soon the hypervisor gets really pissed and steals up to 90% of the CPU. So the only solution so far is restarting the docker containers every 12 hours (not great, not terrible).

Looking to improve this, Iam now experimenting with ZRAM and swappiness and it seems some benefit can be achieved by using some of the Linux kernel feaures. Is there anything else I should look into?

  • cooopsspace@infosec.pub
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    1 year ago

    Wow you’re right. You are a stingy bastard.

    Never run anything on a free tier if you want to keep it. My legit Oracle account got flagged and deleted for no reason so they’re dead to me, and I’ll tell anyone who will listen. They’re thieving assholes and will snatch away free tier the moment it’s convenient for them.

    Do you really need netbird? What for?

    Spend some money, consider it the cost of education

  • SteveTech@programming.dev
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    1 year ago

    If you’re using Oracle cloud (just guessing based off 1GB), they also offer free ARM VMs with 24GB of RAM, and netbird looks to support ARM.

  • mvirts@lemmy.world
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    1 year ago

    Turn on swap! That way more of your actual ram can be used by the application. Yes, it will probably be slow as crud but it should use more memory than it has. If swap is already on… sorry

    • aesir@lemmy.worldOP
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      1 year ago

      I forgot to mention, I had plenty of swap available, now I disabled swap to force zram usage. I still need to see what happens running with both, it’s hard when each trial takes 12-24 hours to show its result.

  • arirr@lemmy.kde.social
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    1 year ago

    Oracle free tier is 24GB of RAM. I hate Oracle as much as the next person, but worst thing they do is shut it off and you have to migrate.

  • axum@kbin.social
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    1 year ago

    Get an oracle cloud account and use their free arm server. You’ll have 24 gb of ram to play with. For free.

    • aesir@lemmy.worldOP
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      1 year ago

      Thanks for the suggestion, but my 24 GB are well employed already. I wanted at least to outsource the VPN manager to a smaller VPS.

  • hatedbad@lemmy.sdf.org
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    1 year ago

    why use docker here? you’re just adding layers of abstraction in an environment that can’t seem to really support them.

    that said, switching to 32bit linux, if the VPS supports it, will save you memory.

    • aesir@lemmy.worldOP
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      1 year ago

      This service consist of several docker containers, without docker I would not even know where to start for deploying it. Maintainance as well would be a mess, totally not an option

      • qjkxbmwvz@lemmy.sdf.org
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        1 year ago

        I think the advice should be taken to heart here — you’re dealing with a userspace problem but you’re trying to get the kernel to make it all better.

        You’ve already mentioned the two big things, compressed RAM and swap; optimizing userspace (or paying for more RAM) may be the only option at some point.

        If you want to get creative, is there a reason you can’t use a local computer for some of these services? An old raspberry pi or similar could potentially run some of your services. You could run some containers on your home server and call it a day. Quick search turned up this https://www.linuxserver.io/blog/routing-docker-host-and-container-traffic-through-wireguard

    • aesir@lemmy.worldOP
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      1 year ago

      I am experimenting with ZRAM, it is indeed better than ZSWAP, that’s why i am asking if any other kernel features can help.

  • onlinepersona@programming.dev
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    1 year ago

    What are you trying to do? I read “hypervisor” and am not sure if you mean the one managing your VPS or if you installed one in your VPS.