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Joined 3 years ago
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Cake day: June 15th, 2023

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  • Morphit @feddit.uktoScience Memes@mander.xyzJust vibing
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    11 hours ago

    Amps are not joules / second;- that would be Watts. Amps = Coulombs / second, and Volts = Joules / Coulomb. That’s why multiplying them gives you power in Watts.

    That’s true instantaneously but as you say, if the current or voltage are alternating then you can’t just use the AC current and voltage to get real power like you can with DC.












  • Not sure I can help with caching but you’re confusing the derivation and build result. Both end up in the nix store but the derivations are just files with the .drv extension. The build artefacts have a hash based on the derivation, but it is different. I think they are both deterministic as long as you don’t change config or update channel/flake dependencies. Can you check both paths in the nix store and try rebuilding?




  • Morphit @feddit.uktolinuxmemes@lemmy.worldoops
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    23 days ago

    There are tools like snapper and btrbk that periodically make snapshots. Since btrfs is a COW filesystem, the live subvolume just stores newer changes on top of the snapshot — it doesn’t need to copy anything until it changes. Only when file data is no-longer referenced is it actually marked free to overwrite. This can make disk usage a bit un-intuitive since you can have large files stuck in snapshots that don’t show up in your live subvolumes but still use up space. It can really save you from serious mess ups and is really cheap in terms of performance. It’s also possible to send snapshots over a network to another machine if you want longer term backups without keeping them on local disks.