Thanks! I tested powertop now, it shows the following “Tunables” that can be toggled between “Good” and “Bad” which I think mean “good for reducing power consumption” and “bad for reducing power consumption”:
PowerTOP 2.8 Overview Idle stats Frequency stats Device stats Device Freq stats Tunables
Bad Wireless Power Saving for interface wlan0
Bad VM writeback timeout
Good Bluetooth device interface status
Good Autosuspend for USB device Qualcomm CDMA Technologies MSM [Qualcomm, Incorporated]
Good Autosuspend for USB device xHCI Host Controller [usb1]
Good Autosuspend for USB device Ultra Fast Media Reader [Generic]
Good Autosuspend for unknown USB device 1-1 (0424:2640)
Good Autosuspend for USB device xHCI Host Controller [usb2]
Good I2C Device 2-001a has no runtime power management
Good Runtime PM for I2C Adapter i2c-2 (30a40000.i2c)
Good Runtime PM for I2C Adapter i2c-3 (30a50000.i2c)
Good Runtime PM for I2C Adapter i2c-0 (30a20000.i2c)
Good Runtime PM for I2C Adapter i2c-1 (30a30000.i2c)
Good I2C Device 3-0010 has no runtime power management
Good I2C Device 1-0060 has no runtime power management
Good Wake-on-lan status for device wlan0
Good Wake-on-lan status for device wwan0
Good Wake-on-lan status for device usb0
I tried setting all of them to “Bad” (which should be good for performance) but so far I did not see any clear effect. Setting the top one, “Wireless Power Saving for interface wlan0” to “Good” seemed to stop WiFi totally, hanging my ssh session. 