Bryan Gardiner 2400191caf nixos/xdg/mime: disable fdatasync when building the XDG MIME database ... Back in 2013, update-mime-database started using fdatasync() to write out its changes after processing each file in /share/mime, with the reasoning that a corrupted database from an interruption midway would be problematic for applications[1]. Unfortunately, this caused a significant regression in the time required to run update-mime-database: commonly from under a second to half a minute or more. This delay affects the time required to build system-path on NixOS, when xdg.mime.enable is true (the default). For example, on one of my systems system-path builds in ~48 seconds, 45 of which are update-mime-database. This makes rapidly building new system configurations not fun. This commit disables the calls to fdatasync(). update-mime-database checks an environment variable, PKGSYSTEM_ENABLE_FSYNC, to determine whether it should sync, and we can set this to false. system-path already only has whatever filesystem commit guarantees that the Nix builder provides. Furthermore, there is no risk of a failed MIME database update messing up existing packages, because this is Nix. (This issue was also reported at and discussed by Debian, Red Hat, and Gentoo at least.) [1] https://bugs.freedesktop.org/show_bug.cgi?id=70366		2019-05-25 21:00:25 -07:00
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autostart.nix
icons.nix
menus.nix
mime.nix	nixos/xdg/mime: disable fdatasync when building the XDG MIME database	2019-05-25 21:00:25 -07:00
sounds.nix