我可以暂停到 RAM。屏幕变黑，然后显示器也进入省电模式。
但是，当暂停时，我系统中的所有风扇都保持开启状态：
- CPU风扇
- 机箱风扇
- GPU风扇
挂起时的内核日志：
[ 1377.806203] PM: suspend entry (s2idle)
[ 1377.809246] Filesystems sync: 0.003 seconds
[ 1377.809249] PM: Preparing system for sleep (s2idle)
[ 1378.070546] Freezing user space processes ... (elapsed 0.003 seconds) done.
[ 1378.073872] OOM killer disabled.
[ 1378.073873] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 1378.075361] PM: Suspending system (s2idle)
[ 1378.075363] printk: Suspending console(s) (use no_console_suspend to debug)
[ 1380.588027] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588031] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588033] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588035] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588037] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588039] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588040] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588042] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588044] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1380.588046] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f2f00
[ 1382.604016] snd_hda_intel 0000:17:00.1: azx_get_response timeout, switching to polling mode: last cmd=0x006f0900
[ 1383.324019] xpad 1-4:1.0: timed out waiting for output URB to complete, killing
[ 1383.324624] PM: suspend of devices complete after 5248.932 msecs
[ 1383.324629] PM: start suspend of devices complete after 5249.286 msecs
[ 1383.326763] PM: late suspend of devices complete after 2.130 msecs
[ 1383.383948] PM: noirq suspend of devices complete after 56.985 msecs
[ 1383.383951] PM: suspend-to-idle
唤醒时的内核日志：
[ 1399.984106] PM: Timekeeping suspended for 15.947 seconds
[ 1399.984279] PM: resume from suspend-to-idle
[ 1400.044023] PM: noirq resume of devices complete after 59.737 msecs
[ 1400.045312] PM: early resume of devices complete after 1.170 msecs
[ 1400.045645] pci 0000:16:05.0: disabled boot interrupts on device [8086:2034]
[ 1400.045766] pci 0000:64:05.0: disabled boot interrupts on device [8086:2034]
[ 1400.045831] pci 0000:b2:05.0: disabled boot interrupts on device [8086:2034]
[ 1400.212010] snd_hda_intel 0000:17:00.1: azx_get_response timeout, switching to single_cmd mode: last cmd=0x006f0900
[ 1400.212119] azx_single_wait_for_response: 6309 callbacks suppressed
[ 1400.212220] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.212522] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.212818] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.213112] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.213407] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.213701] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.213996] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.214291] snd_hda_codec_hdmi hdaudioC0D0: HDMI: invalid ELD buf size -1
[ 1400.292802] nvme nvme0: 16/0/0 default/read/poll queues
[ 1401.944040] pcieport 0000:b2:00.0: pciehp: Timeout on hotplug command 0x07d5 (issued 1960 msec ago)
[ 1401.944044] pcieport 0000:b2:01.0: pciehp: Timeout on hotplug command 0x07d5 (issued 1960 msec ago)
[ 1401.944047] pcieport 0000:b2:03.0: pciehp: Timeout on hotplug command 0x07d5 (issued 1960 msec ago)
[ 1401.944051] pcieport 0000:b2:02.0: pciehp: Timeout on hotplug command 0x07d5 (issued 1960 msec ago)
[ 1401.944114] PM: resume of devices complete after 1898.804 msecs
[ 1401.945342] PM: Finishing wakeup.
[ 1401.945343] OOM killer enabled.
[ 1401.945344] Restarting tasks ... done.
[ 1401.956420] rfkill: input handler enabled
[ 1401.956718] PM: suspend exit
[ 1402.228867] snd_hdac_bus_update_rirb: 430 callbacks suppressed
[ 1402.228874] snd_hda_intel 0000:17:00.1: spurious response 0x80000000:0x0, last cmd=0x6f0900
[ 1402.269012] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x6f0900
[ 1402.285794] rfkill: input handler disabled
[ 1403.352002] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x820000
[ 1403.352037] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x820000
[ 1403.375973] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x1f0500
[ 1403.376011] snd_hda_intel 0000:17:00.1: spurious response 0x233:0x0, last cmd=0x1f0500
[ 1403.449159] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x1f0500
[ 1403.449198] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x4f0015
[ 1403.449239] snd_hda_intel 0000:17:00.1: spurious response 0x3:0x0, last cmd=0x473500
[ 1403.449281] snd_hda_intel 0000:17:00.1: spurious response 0x0:0x0, last cmd=0x470700
[ 1405.084501] igb 0000:04:00.0 eno1: igb: eno1 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
我检查了 Supermicro X11SRM-F BIOS 设置，但没有列出挂起内存选项。此外，挂起功能似乎确实有效，只是没有关闭风扇。
我尝试过扩展 APICBIOS 中的选项，结果相同。
更新：
看起来，系统使用的暂停类型是导致此问题的原因。
系统日志表明已使用 s2idle，这不是一种深度睡眠。
检查其他支持的模式可以得到：
$ cat /sys/power/mem_sleep
[s2idle]
...令人失望的是，这意味着其他模式不可用。目前尚不清楚这里的限制因素是什么。主板？BIOS？
从内核：
ACPI: (supports S0 S4 S5)
所以没有 S3，那意味着没有暂停到 RAM？
操作系统：Ubuntu 20.04.1 LTS
中央处理器：至强W2140B
母板：超微 X11XRM-F
答案1
系统没有执行挂起至内存 (ACPI S3)，它停留在 ACPI S0。
从内核日志中：
ACPI: (supports S0 S4 S5)
来自 Supermicro 支持：
“X11SRM-F 是一款旨在支持全天候使用的服务器主板。它不支持 S3 状态。”
因此，我们可以得出结论，该主板无法支持挂起到 RAM 的功能。