.. Copyright 2013-2023 Lawrence Livermore National Security, LLC and other Spack Project Developers. See the top-level COPYRIGHT file for details. SPDX-License-Identifier: (Apache-2.0 OR MIT) .. _binary_caches: ============ Build Caches ============ Some sites may encourage users to set up their own test environments before carrying out central installations, or some users may prefer to set up these environments on their own motivation. To reduce the load of recompiling otherwise identical package specs in different installations, installed packages can be put into build cache tarballs, pushed to your Spack mirror and then downloaded and installed by others. Whenever a mirror provides prebuilt packages, Spack will take these packages into account during concretization and installation, making ``spack install`` significantly faster. .. note:: We use the terms "build cache" and "mirror" often interchangeably. Mirrors are used during installation both for sources and prebuilt packages. Build caches refer to mirrors that provide prebuilt packages. ---------------------- Creating a build cache ---------------------- Build caches are created via: .. code-block:: console $ spack buildcache push This command takes the locally installed spec and its dependencies, and creates tarballs of their install prefixes. It also generates metadata files, signed with GPG. These tarballs and metadata files are then pushed to the provided binary cache, which can be a local directory or a remote URL. Here is an example where a build cache is created in a local directory named "spack-cache", to which we push the "ninja" spec: .. code-block:: console $ spack buildcache push ./spack-cache ninja ==> Pushing binary packages to file:///home/spackuser/spack/spack-cache/build_cache Note that ``ninja`` must be installed locally for this to work. Once you have a build cache, you can add it as a mirror, discussed next. --------------------------------------- Finding or installing build cache files --------------------------------------- To find build caches or install build caches, a Spack mirror must be configured with: .. code-block:: console $ spack mirror add Both web URLs and local paths on the filesystem can be specified. In the previous example, you might add the directory "spack-cache" and call it ``mymirror``: .. code-block:: console $ spack mirror add mymirror ./spack-cache You can see that the mirror is added with ``spack mirror list`` as follows: .. code-block:: console $ spack mirror list mymirror file:///home/spackuser/spack/spack-cache spack-public https://spack-llnl-mirror.s3-us-west-2.amazonaws.com/ At this point, you've create a buildcache, but spack hasn't indexed it, so if you run ``spack buildcache list`` you won't see any results. You need to index this new build cache as follows: .. code-block:: console $ spack buildcache update-index ./spack-cache Now you can use list: .. code-block:: console $ spack buildcache list ==> 1 cached build. -- linux-ubuntu20.04-skylake / gcc@9.3.0 ------------------------ ninja@1.10.2 With ``mymirror`` configured and an index available, Spack will automatically use it during concretization and installation. That means that you can expect ``spack install ninja`` to fetch prebuilt packages from the mirror. Let's verify by re-installing ninja: .. code-block:: console $ spack uninstall ninja $ spack install ninja ==> Installing ninja-1.11.1-yxferyhmrjkosgta5ei6b4lqf6bxbscz ==> Fetching file:///home/spackuser/spack/spack-cache/build_cache/linux-ubuntu20.04-skylake-gcc-9.3.0-ninja-1.10.2-yxferyhmrjkosgta5ei6b4lqf6bxbscz.spec.json.sig gpg: Signature made Do 12 Jan 2023 16:01:04 CET gpg: using RSA key 61B82B2B2350E171BD17A1744E3A689061D57BF6 gpg: Good signature from "example (GPG created for Spack) " [ultimate] ==> Fetching file:///home/spackuser/spack/spack-cache/build_cache/linux-ubuntu20.04-skylake/gcc-9.3.0/ninja-1.10.2/linux-ubuntu20.04-skylake-gcc-9.3.0-ninja-1.10.2-yxferyhmrjkosgta5ei6b4lqf6bxbscz.spack ==> Extracting ninja-1.10.2-yxferyhmrjkosgta5ei6b4lqf6bxbscz from binary cache ==> ninja: Successfully installed ninja-1.11.1-yxferyhmrjkosgta5ei6b4lqf6bxbscz Search: 0.00s. Fetch: 0.17s. Install: 0.12s. Total: 0.29s [+] /home/harmen/spack/opt/spack/linux-ubuntu20.04-skylake/gcc-9.3.0/ninja-1.11.1-yxferyhmrjkosgta5ei6b4lqf6bxbscz It worked! You've just completed a full example of creating a build cache with a spec of interest, adding it as a mirror, updating its index, listing the contents, and finally, installing from it. By default Spack falls back to building from sources when the mirror is not available or when the package is simply not already available. To force Spack to only install prebuilt packages, you can use .. code-block:: console $ spack install --use-buildcache only For example, to combine all of the commands above to add the E4S build cache and then install from it exclusively, you would do: .. code-block:: console $ spack mirror add E4S https://cache.e4s.io $ spack buildcache keys --install --trust $ spack install --use-buildcache only We use ``--install`` and ``--trust`` to say that we are installing keys to our keyring, and trusting all downloaded keys. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ List of popular build caches ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * `Extreme-scale Scientific Software Stack (E4S) `_: `build cache `_ ---------- Relocation ---------- Initial build and later installation do not necessarily happen at the same location. Spack provides a relocation capability and corrects for RPATHs and non-relocatable scripts. However, many packages compile paths into binary artifacts directly. In such cases, the build instructions of this package would need to be adjusted for better re-locatability. .. _cmd-spack-buildcache: -------------------- ``spack buildcache`` -------------------- ^^^^^^^^^^^^^^^^^^^^^^^^^^^ ``spack buildcache push`` ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Create tarball of installed Spack package and all dependencies. Tarballs are checksummed and signed if gpg2 is available. Places them in a directory ``build_cache`` that can be copied to a mirror. Commands like ``spack buildcache install`` will search Spack mirrors for build_cache to get the list of build caches. ============== ======================================================================================================================== Arguments Description ============== ======================================================================================================================== ```` list of partial specs or hashes with a leading ``/`` to match from installed packages and used for creating build caches ``-d `` directory in which ``build_cache`` directory is created, defaults to ``.`` ``-f`` overwrite ``.spack`` file in ``build_cache`` directory if it exists ``-k `` the key to sign package with. In the case where multiple keys exist, the package will be unsigned unless ``-k`` is used. ``-r`` make paths in binaries relative before creating tarball ``-y`` answer yes to all create unsigned ``build_cache`` questions ============== ======================================================================================================================== ^^^^^^^^^^^^^^^^^^^^^^^^^ ``spack buildcache list`` ^^^^^^^^^^^^^^^^^^^^^^^^^ Retrieves all specs for build caches available on a Spack mirror. ============== ===================================================================================== Arguments Description ============== ===================================================================================== ```` list of partial package specs to be matched against specs downloaded for build caches ============== ===================================================================================== E.g. ``spack buildcache list gcc`` with print only commands to install ``gcc`` package(s) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ``spack buildcache install`` ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Retrieves all specs for build caches available on a Spack mirror and installs build caches with specs matching the specs input. ============== ============================================================================================== Arguments Description ============== ============================================================================================== ```` list of partial package specs or hashes with a leading ``/`` to be installed from build caches ``-f`` remove install directory if it exists before unpacking tarball ``-y`` answer yes to all to don't verify package with gpg questions ============== ============================================================================================== ^^^^^^^^^^^^^^^^^^^^^^^^^ ``spack buildcache keys`` ^^^^^^^^^^^^^^^^^^^^^^^^^ List public keys available on Spack mirror. ========= ============================================== Arguments Description ========= ============================================== ``-i`` trust the keys downloaded with prompt for each ``-y`` answer yes to all trust all keys downloaded ========= ==============================================