为什么我的apt-get更新如此大？
可能重复：
apt-get更新列表的大小太大了
在干净安装12.04（Release Candidate）并接受所有更新和升级到今天之后，我发现sudo apt-get update总是获取MB范围内的信息，大约12 MB，而sudo apt-get upgrade主要没有任何东西可以下载。
我看到的三个最大的东西是：
http://archive.ubuntu.com precise/universe Sources [5,019 kB] http://archive.ubuntu.com precise/main i386 Packages [1,274 KB] http://archive.ubuntu.com precise/universe i386 Packages [4,796 KB]
我很确定sudo apt-get update提取不是11.10那么大，甚至很少超过1 MB。
我的问题是：这些大型提取仅仅因为12.04是最近的还是这些大型更新是常态？
编辑：为了回应迈克的回答，我发布了几个屏幕截图： 
第二次编辑：我包括我现在的/etc/apt/sources.list 。 这是在我取消之前在“其他软件”图像中勾选的“源代码”条目之后。
# deb cdrom:[Ubuntu 12.04 LTS _Precise Pangolin_ - Beta i386 (20120421)]/ precise main restricted # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://archive.ubuntu.com/ubuntu precise main restricted deb-src http://archive.ubuntu.com/ubuntu precise main restricted ## Major bug fix updates produced after the final release of the ## distribution. deb http://archive.ubuntu.com/ubuntu precise-updates main restricted deb-src http://archive.ubuntu.com/ubuntu precise-updates main restricted ## NB software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://archive.ubuntu.com/ubuntu precise universe deb-src http://archive.ubuntu.com/ubuntu precise universe deb http://archive.ubuntu.com/ubuntu precise-updates universe deb-src http://archive.ubuntu.com/ubuntu precise-updates universe ## NB software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://archive.ubuntu.com/ubuntu precise multiverse deb-src http://archive.ubuntu.com/ubuntu precise multiverse deb http://archive.ubuntu.com/ubuntu precise-updates multiverse deb-src http://archive.ubuntu.com/ubuntu precise-updates multiverse ## NB software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://archive.ubuntu.com/ubuntu precise-backports main restricted universe multiverse deb-src http://archive.ubuntu.com/ubuntu precise-backports main restricted universe multiverse deb http://archive.ubuntu.com/ubuntu precise-security main restricted deb-src http://archive.ubuntu.com/ubuntu precise-security main restricted deb http://archive.ubuntu.com/ubuntu precise-security universe deb-src http://archive.ubuntu.com/ubuntu precise-security universe deb http://archive.ubuntu.com/ubuntu precise-security multiverse deb-src http://archive.ubuntu.com/ubuntu precise-security multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu precise partner # deb-src http://archive.canonical.com/ubuntu precise partner ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software. deb http://extras.ubuntu.com/ubuntu precise main # deb-src http://extras.ubuntu.com/ubuntu precise main
第三次编辑：对于记录， lsb_release -a显示
No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 12.04 LTS Release: 12.04 Codename: precise
第四次编辑（20120512）：这是我今天看到的apt-get update的输出：
Inspiron-1545：〜$快
Ign http://archive.ubuntu.com precise InRelease Ign http://archive.ubuntu.com precise-updates InRelease Ign http://archive.ubuntu.com precise-security InRelease Ign http://archive.canonical.com precise InRelease Ign http://extras.ubuntu.com precise InRelease Ign http://ppa.launchpad.net precise InRelease Ign http://ppa.launchpad.net precise InRelease Get:1 http://archive.ubuntu.com precise Release.gpg [198 B] Get:2 http://archive.ubuntu.com precise-updates Release.gpg [198 B] Hit http://archive.canonical.com precise Release.gpg Hit http://extras.ubuntu.com precise Release.gpg Hit http://ppa.launchpad.net precise Release.gpg Get:3 http://archive.ubuntu.com precise-security Release.gpg [198 B] Get:4 http://archive.ubuntu.com precise Release [49.6 kB] Hit http://archive.canonical.com precise Release Hit http://extras.ubuntu.com precise Release Hit http://ppa.launchpad.net precise Release.gpg Hit http://archive.canonical.com precise/partner i386 Packages Hit http://extras.ubuntu.com precise/main i386 Packages Hit http://ppa.launchpad.net precise Release Get:5 http://archive.ubuntu.com precise-updates Release [49.6 kB] Ign http://archive.canonical.com precise/partner TranslationIndex Ign http://extras.ubuntu.com precise/main TranslationIndex Hit http://ppa.launchpad.net precise Release Get:6 http://archive.ubuntu.com precise-security Release [49.6 kB] Hit http://ppa.launchpad.net precise/main i386 Packages Ign http://ppa.launchpad.net precise/main TranslationIndex Hit http://ppa.launchpad.net precise/main i386 Packages Ign http://ppa.launchpad.net precise/main TranslationIndex Ign http://archive.canonical.com precise/partner Translation-en_IN Ign http://extras.ubuntu.com precise/main Translation-en_IN Ign http://archive.canonical.com precise/partner Translation-en Ign http://extras.ubuntu.com precise/main Translation-en Ign http://ppa.launchpad.net precise/main Translation-en_IN Ign http://ppa.launchpad.net precise/main Translation-en Ign http://ppa.launchpad.net precise/main Translation-en_IN Get:7 http://archive.ubuntu.com precise/main i386 Packages [1,274 kB] Ign http://ppa.launchpad.net precise/main Translation-en Get:8 http://archive.ubuntu.com precise/restricted i386 Packages [8,431 B] Get:9 http://archive.ubuntu.com precise/universe i386 Packages [4,796 kB] Get:10 http://archive.ubuntu.com precise/multiverse i386 Packages [121 kB] Hit http://archive.ubuntu.com precise/main TranslationIndex Hit http://archive.ubuntu.com precise/multiverse TranslationIndex Hit http://archive.ubuntu.com precise/restricted TranslationIndex Hit http://archive.ubuntu.com precise/universe TranslationIndex Get:11 http://archive.ubuntu.com precise-updates/main i386 Packages [96.5 kB] Get:12 http://archive.ubuntu.com precise-updates/main i386 Packages [96.5 kB] Get:13 http://archive.ubuntu.com precise-updates/restricted i386 Packages [770 B] Get:14 http://archive.ubuntu.com precise-updates/universe i386 Packages [27.7 kB] Get:15 http://archive.ubuntu.com precise-updates/multiverse i386 Packages [1,393 B] Hit http://archive.ubuntu.com precise-updates/main TranslationIndex Hit http://archive.ubuntu.com precise-updates/multiverse TranslationIndex Hit http://archive.ubuntu.com precise-updates/restricted TranslationIndex Hit http://archive.ubuntu.com precise-updates/universe TranslationIndex Get:16 http://archive.ubuntu.com precise-security/main i386 Packages [32.9 kB] Get:17 http://archive.ubuntu.com precise-security/restricted i386 Packages [14 B] Get:18 http://archive.ubuntu.com precise-security/universe i386 Packages [8,594 B] Get:19 http://archive.ubuntu.com precise-security/multiverse i386 Packages [1,393 B] Hit http://archive.ubuntu.com precise-security/main TranslationIndex Hit http://archive.ubuntu.com precise-security/multiverse TranslationIndex Hit http://archive.ubuntu.com precise-security/restricted TranslationIndex Hit http://archive.ubuntu.com precise-security/universe TranslationIndex Hit http://archive.ubuntu.com precise/main Translation-en Hit http://archive.ubuntu.com precise/multiverse Translation-en Hit http://archive.ubuntu.com precise/restricted Translation-en Hit http://archive.ubuntu.com precise/universe Translation-en Hit http://archive.ubuntu.com precise-updates/main Translation-en Hit http://archive.ubuntu.com precise-updates/multiverse Translation-en Hit http://archive.ubuntu.com precise-updates/restricted Translation-en Hit http://archive.ubuntu.com precise-updates/universe Translation-en Hit http://archive.ubuntu.com precise-security/main Translation-en Hit http://archive.ubuntu.com precise-security/multiverse Translation-en Hit http://archive.ubuntu.com precise-security/restricted Translation-en Hit http://archive.ubuntu.com precise-security/universe Translation-en Fetched 6,494 kB in 2min 51s (37.9 kB/s) Reading package lists... Done Working... No files to download. Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. -e Done! Verify that all packages were installed successfully. If errors are found, run apt-get clean as root and try again using apt-get directly.
（在第一行fast是因为我使用apt-fast而不是apt-get ）
我禁用了apt.conf的deb-src行，每个mikew答案都是如此。 就像你一样，它降低了大约6MB。
然后我注意到，当apt获取包信息时，它通过192.168.1.3 – 我的squid-deb-proxy服务器（运行11.10;我还没有进行升级）。 从客户端卸载squid-deb-proxy-client使信息下载大小恢复正常。
编辑：Aaand它回到了原来的行为。 我还检查了我的Mac上的虚拟机（它出来的那天刚刚安装好的稳定版），我不时地启动它; 包更新信息也是一个很大的下载。 我将把这个答案留下来，只是为了certificate这个解决方案不起作用。 除此之外，我被困住了。
也许不同的是源包。 尝试在“软件源”窗口中禁用它们，或者编辑/etc/apt/sources.list ，并注释掉以deb-src开头的行，…即，如果您不需要源代码。