Why does nixos-tools use twice the memory of comparable tools?

NIr/nixos-tools·posted by tang_hao·2 hours agoJobs

Short version: nixos-tools needs almost no tuning at small and medium scale — the point where it starts to hurt is much further out than most people assume. Full measurements below.

Worth noting: the official docs do cover this, just in a very inconspicuous spot. I only found it reading the source comments, where the author explains the reasoning — roughly "so that it degrades into predictable behaviour in extreme cases".

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4 comments

Rrase·12 minutes ago

Worth learning from this debugging approach. We went straight at the logs and took a much longer route.

501

Kkernel_panic·28 minutes ago

There is actually a simpler fix that needs no architecture change: move this check up to the gateway and the problem disappears. The cost is one extra lookup at the gateway.

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Oops_wang·1 hour agoedited

A question: what changes in a container with a 512Mi memory limit? That is how we run it in production.

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Wwinter·28 minutes ago

Saved. I am reworking this area this week — this saves a lot of wrong turns.

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NixOS · Toolchain · Why does nixos-tools use twice the memory of comparable tools?

Why does nixos-tools use twice the memory of comparable tools?

4 comments