我正在使用 Ubuntu 18.04（Asus_M4A88T-M-USB3 主板，配备 AMD Phenom(tm) II X4 945 处理器和 8GB ddr3 RAM），与 16.04 相比，启动过程耗时很长。如何减少启动时间。或者 18.04 可以吗？
精选信息
dmesg
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[ 9.108094] lp0: using parport0 (interrupt-driven).
[ 18.865467] audit: type=1400 audit(1540755431.877:2): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/bin/man" pid=381 comm="apparmor_parser"
......
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[ 29.966625] IPv6: ADDRCONF(NETDEV_CHANGE): enp2s0: link becomes ready
[ 35.808136] rfkill: input handler disabled
[ 43.642588] nouveau 0000:01:00.0: Direct firmware load for nouveau/nva8_fuc084 failed with error -2
[ 43.642595] nouveau 0000:01:00.0: Direct firmware load for nouveau/nva8_fuc084d failed with error -2
[ 43.642597] nouveau 0000:01:00.0: msvld: unable to load firmware data
[ 43.642601] nouveau 0000:01:00.0: msvld: init failed, -19
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systemd-analyzed
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Startup finished in 5.817s (kernel) + 50.562s (userspace) = 56.380s
graphical.target reached after 42.230s in userspace
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systemd-analyze blame
26.244s apt-daily.service
20.879s plymouth-quit-wait.service
14.776s dev-sda4.device
13.684s systemd-journal-flush.service
10.644s systemd-modules-load.service
8.845s dev-loop0.device
8.836s dns-clean.service
8.702s apparmor.service
8.661s systemd-udevd.service
8.467s binfmt-support.service
7.784s proc-sys-fs-binfmt_misc.mount
7.714s snap-core-5662.mount
......
......
答案1
我尝试了很多方法，但只有在将 nouveau 更改为 nvidia-340 后，启动时间才减少了约一半。
消息
[ 8.073745] systemd-journald 272]: Received request to flush runtime journal from PID 1
[ 18.353802] shpchp: Standard Hot Plug PCI Controller Driver version: 0.4
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[ 29.241267] resource sanity check: requesting [mem 0x000c0000-0x000fffff], which spans more than PCI Bus 0000:00 mem 0x000d0000-0x000dffff window]
[ 29.241405] caller os_map_kernel_space+0x86/0xb0 [nvidia] mapping multiple BARs
[ 29.362723] r8169 0000:02:00.0 enp2s0: link up
[ 29.362731] IPv6: ADDRCONF(NETDEV_CHANGE): enp2s0: link becomes ready
[ 34.017794] rfkill: input handler disabled
:~$
systemd-分析
Startup finished in 5.138s (kernel) + 27.173s (userspace) = 32.311s
graphical.target reached after 27.164s in userspace
systemd-analyze 责备
15.847s systemd-journal-flush.service
11.869s dev-sda4.device
11.011s keyboard-setup.service
10.145s systemd-sysctl.service
8.805s systemd-udevd.service