From b0328c244dd15da9e45f4e95d900c81fe0c47dda Mon Sep 17 00:00:00 2001 From: Renzo Carbonara Date: Tue, 9 Jan 2018 22:40:07 +0100 Subject: [PATCH] nix.conf: builders-use-substitutes Fixes #937 --- doc/manual/command-ref/conf-file.xml | 14 ++++++++++++++ src/build-remote/build-remote.cc | 6 ++++-- src/libstore/globals.hh | 5 +++++ 3 files changed, 23 insertions(+), 2 deletions(-) diff --git a/doc/manual/command-ref/conf-file.xml b/doc/manual/command-ref/conf-file.xml index 87f05fb1c..2ddca991f 100644 --- a/doc/manual/command-ref/conf-file.xml +++ b/doc/manual/command-ref/conf-file.xml @@ -321,6 +321,20 @@ false. + builders-use-substitutes + + If set to true, Nix will instruct + remote build machines to use their own binary substitutes if available. In + practical terms, this means that remote hosts will fetch as many build + dependencies as possible from their own substitutes (e.g, from + cache.nixos.org), instead of waiting for this host to + upload them all. This can drastically reduce build times if the network + connection between this computer and the remote build host is slow. Defaults + to false. + + + + fallback If set to true, Nix will fall diff --git a/src/build-remote/build-remote.cc b/src/build-remote/build-remote.cc index 445006b32..df579729a 100644 --- a/src/build-remote/build-remote.cc +++ b/src/build-remote/build-remote.cc @@ -218,9 +218,11 @@ connected: signal(SIGALRM, old); } + auto substitute = settings.buildersUseSubstitutes ? Substitute : NoSubstitute; + { Activity act(*logger, lvlTalkative, actUnknown, fmt("copying dependencies to '%s'", storeUri)); - copyPaths(store, ref(sshStore), inputs, NoRepair, NoCheckSigs); + copyPaths(store, ref(sshStore), inputs, NoRepair, NoCheckSigs, substitute); } uploadLock = -1; @@ -240,7 +242,7 @@ connected: if (!missing.empty()) { Activity act(*logger, lvlTalkative, actUnknown, fmt("copying outputs from '%s'", storeUri)); setenv("NIX_HELD_LOCKS", concatStringsSep(" ", missing).c_str(), 1); /* FIXME: ugly */ - copyPaths(ref(sshStore), store, missing, NoRepair, NoCheckSigs); + copyPaths(ref(sshStore), store, missing, NoRepair, NoCheckSigs, substitute); } return; diff --git a/src/libstore/globals.hh b/src/libstore/globals.hh index ae4b78a01..af72f7b1e 100644 --- a/src/libstore/globals.hh +++ b/src/libstore/globals.hh @@ -138,6 +138,11 @@ public: Setting builders{this, "@" + nixConfDir + "/machines", "builders", "A semicolon-separated list of build machines, in the format of nix.machines."}; + Setting buildersUseSubstitutes{this, false, "builders-use-substitutes", + "Whether build machines should use their own substitutes for obtaining " + "build dependencies if possible, rather than waiting for this host to " + "upload them."}; + Setting reservedSize{this, 8 * 1024 * 1024, "gc-reserved-space", "Amount of reserved disk space for the garbage collector."};