在日常支持中，我们可能需要安装Python、GCC等工具。通常步骤是
找到官网，下载需要的包传到目的服务器解压./configure && make && make install一圈下来，耗时不少。
Spack是什么？它是一个自动化包管理器，支持管理Linux、MacOS上的包。
Spack能做什么？Spack能使得上述步骤自动化，并自动生成modulefile（Environment Modules或Lmod的，都可以生成）——无论是对于广泛使用的开源包，还是有知识产权保护的有限范围分发包，还是处于研发阶段的内部包，它都能轻松搞定。
举例本文以安装开源包Python为例，来感受一下自动安装的魅力，
先看已有的Python版本
[thesre@localhost ~]$ module avail python-------------------------------------------- /app/spack-0.16.2/share/spack/modules/linux-centos7-sandybridge --------------------------------------------python-3.8.6-gcc-9.4.0-x7ebx7b [thesre@localhost ~]$安装Python 3.9.0
[thesre@localhost ~]$ spack -k install python@3.9.0==> Warning: You asked for --insecure. Will NOT check SSL certificates.[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/libiconv-1.16-qp6xhw7243p2s3jrfygxcor3f723zy4y[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/libbsd-0.10.0-ot7ls7bw4butgierpa4cmjluqvsjoaji[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/pkgconf-1.7.3-vdqtrqwkkhqy3g4i5jjj3t3siptzpgxm[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/xz-5.2.5-ds3jrbkvzlrnklirwgnagoj67ngbx6gb[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/zlib-1.2.11-wrpx7fqamc562dxcn3qwyl5dzfswl5qh[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/libffi-3.3-s7scryukxbekp7u3hlq5czx5fyz2cyzi[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/libuuid-1.0.3-rssfovgso7ojag5ybguj4qpoptzyliab[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/berkeley-db-18.1.40-gfcdrmlydcd4smrmzkziudw6zedihsmv[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/diffutils-3.7-qhfscuxrwvf5y3y3jywz5fiqqgvy6wvj[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/tar-1.32-n6b45i35ks4is5u5taaqd6mzfw44fzlk[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/expat-2.2.10-cal2lrbnkmhqomqhpw4buidkwd256fvu[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/ncurses-6.2-idwc6kcoigxcy43iau4bmlvkocu4olg5[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/libxml2-2.9.10-miqastwta7pzpo4nvqt2bwnkyohwute7[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/bzip2-1.0.8-bt2hrgk32n4zue4w53q4ev7ylidvyv6e[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/readline-8.0-cf4ys6umtgnbq42uxy55ar6yrko2cae5[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/gettext-0.21-cnwqlvg22ivf2a6cygxcphkmx4l5m36p[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/sqlite-3.33.0-wbvmbd6rjewg6fqpciwa72slwpbinhac[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/gdbm-1.18.1-brzlhvhm5mppt7aml2yqz5tlztqrolne[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/perl-5.32.0-gg2xi5suigorukjnv3irvkgv6ebsb2st[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/openssl-1.1.1h-7p3yykxrgamue5lapcnfeh5zhkhohipr==> Installing python-3.9.0-wz6q56w5ytjm5mh2us44r2df5ntcwvfl==> No binary for python-3.9.0-wz6q56w5ytjm5mh2us44r2df5ntcwvfl found: installing from source==> Using cached archive: /app/spack-0.16.2/var/spack/cache/_source-cache/archive/df/df796b2dc8ef085edae2597a41c1c0a63625ebd92487adaef2fed22b567873e8.tgz==> python: Executing phase: 'autoreconf'==> python: Executing phase: 'configure'==> python: Executing phase: 'build'==> python: Executing phase: 'install'[+] /app/spack-0.16.2/opt/spack/linux-centos7-sandybridge/gcc-9.4.0/python-3.9.0-wz6q56w5ytjm5mh2us44r2df5ntcwvfl[thesre@localhost ~]$可以看到多了一个版本，是刚刚安装的Python 3.9.0，其modulename为python-3.9.0-gcc-9.4.0-wz6q56w
[thesre@localhost ~]$ module avail python-------------------------------------------- /app/spack-0.16.2/share/spack/modules/linux-centos7-sandybridge --------------------------------------------python-3.8.6-gcc-9.4.0-x7ebx7b python-3.9.0-gcc-9.4.0-wz6q56w Spack简介101资料：https://spack-tutorial.readthedocs.io/en/latest/#tutorial-spack-101
spack能为
OS版本架构包版本不同编译器包本身的不同编译选项的组合自动生成依赖DAG（单向无环图），并为安装的每一个包名自动打上哈希码，以确保不会冲突。
以上面例子为例，安装Python 3.9.0，并装上了其n个依赖包（全都已经安装好了的）。假如将上述组合中的任何一个更改，都会生成一个新的DAG。