From faa855824058cfa01c367786051fa7e7cd1ee63c Mon Sep 17 00:00:00 2001 From: David Arnold Date: Tue, 16 Mar 2021 18:01:29 -0500 Subject: [PATCH] iso: document iso cache / closures (speed!) --- doc/start/iso.md | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/doc/start/iso.md b/doc/start/iso.md index 1d28e4f..daccfec 100644 --- a/doc/start/iso.md +++ b/doc/start/iso.md @@ -46,6 +46,18 @@ _Note: the [static link-local IPv6 address][staticLLA] and [MulticastDNS][mDNS] configured on the live installer. If you wish to enable [MulticastDNS][mDNS] for your environment, you ought to configure that in a regular [profile](../../profiles)._ +## ISO image nix store & cache + +The iso image holds the store to the live environment and _also_ acts as a binay cache +to the installer. To considerably speed up things, the image already includes all flake +`inputs` as well as the `devshell` closures. + +While you _could_ provision any machine with a single stick, a bespoke iso maximises +those local cache hits. + +For hosts that don't differ too much, a common usb stick might be ok, whereas when +there are bigger differences, a bespoke usb stick will be considerably faster. + ## EUI-64 LLA & Host Identity The iso's IPv6 Link Local Address (LLA) is configured with a static 64-bit Extended @@ -97,11 +109,6 @@ $ flk install NixOS --impure # use same host as above -_Note: You _could_ install another machine than the one your iso was built for, -but the iso doesn't carry all the necesary build artifacts so the target would -start to build the missing parts on demand instead of substituting them from -the iso itself._ - [manual]: https://nixos.org/manual/nixos/stable/index.html#sec-installation-partitioning [mDNS]: https://en.wikipedia.org/wiki/Multicast_DNS [NDP]: https://en.wikipedia.org/wiki/Neighbor_Discovery_Protocol