diff options
Diffstat (limited to 'doc/guix.texi')
| -rw-r--r-- | doc/guix.texi | 35 |
1 files changed, 19 insertions, 16 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 91d3860978..0b79a49814 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -1043,29 +1043,31 @@ When desired, the build daemon can @dfn{offload} derivation builds to other machines running Guix, using the @code{offload} @dfn{build hook}@footnote{This feature is available only when @uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is -present.}. When that -feature is enabled, a list of user-specified build machines is read from -@file{/etc/guix/machines.scm}; every time a build is requested, for -instance via @code{guix build}, the daemon attempts to offload it to one -of the machines that satisfy the constraints of the derivation, in -particular its system type---e.g., @file{x86_64-linux}. Missing -prerequisites for the build are copied over SSH to the target machine, -which then proceeds with the build; upon success the output(s) of the -build are copied back to the initial machine. +present.}. When that feature is enabled, a list of user-specified build +machines is read from @file{/etc/guix/machines.scm}; every time a build +is requested, for instance via @code{guix build}, the daemon attempts to +offload it to one of the machines that satisfy the constraints of the +derivation, in particular its system types---e.g., @code{x86_64-linux}. +A single machine can have multiple system types, either because its +architecture natively supports it, via emulation (@pxref{Transparent +Emulation with QEMU}), or both. Missing prerequisites for the build are +copied over SSH to the target machine, which then proceeds with the +build; upon success the output(s) of the build are copied back to the +initial machine. The @file{/etc/guix/machines.scm} file typically looks like this: @lisp (list (build-machine (name "eightysix.example.org") - (system "x86_64-linux") + (systems (list "x86_64-linux" "i686-linux")) (host-key "ssh-ed25519 AAAAC3Nza@dots{}") (user "bob") (speed 2.)) ;incredibly fast! (build-machine (name "armeight.example.org") - (system "aarch64-linux") + (systems (list "aarch64-linux")) (host-key "ssh-rsa AAAAB3Nza@dots{}") (user "alice") (private-key @@ -1075,8 +1077,8 @@ The @file{/etc/guix/machines.scm} file typically looks like this: @noindent In the example above we specify a list of two build machines, one for -the @code{x86_64} architecture and one for the @code{aarch64} -architecture. +the @code{x86_64} and @code{i686} architectures and one for the +@code{aarch64} architecture. In fact, this file is---not surprisingly!---a Scheme file that is evaluated when the @code{offload} hook is started. Its return value @@ -1096,8 +1098,9 @@ builds. The important fields are: @item name The host name of the remote machine. -@item system -The system type of the remote machine---e.g., @code{"x86_64-linux"}. +@item systems +The system types the remote machine supports---e.g., @code{(list +"x86_64-linux" "i686-linux")}. @item user The user account to use when connecting to the remote machine over SSH. @@ -25025,7 +25028,7 @@ Maximum number of backup files to keep. Defaults to @samp{3} @end deftypevr - +@node Transparent Emulation with QEMU @subsubheading Transparent Emulation with QEMU @cindex emulation |