Reducing SATA power consumption

[gb00s]

Want to share an article I found about the power consumption of SATA drives in 'med_power_with_dipm' mode.

Link1: Reducing SATA power consumption | Insanity Industries
Link2: libata: Add new med_power_with_dipm link_power_management_policy setting - Patchwork

I wasn't aware of this mode available in the Linux kernel.

 

[fossxplorer]

Interesting, totally new to me. I will likely test it on my laptop.

 

[Stephan]

This will not work on some configurations, producing write errors and ATA bus errors in kernel log. If you use it, make sure to watch your system log like a HAWK for some days for anything remotely suspicious. There is a reason this is not activated by default.

Also the usually used udev-rule produces errors when USB thumb drivers are inserted, those do not have this tweakable property and the kernel will complain. This udev rule limits the tweaks to AHCI ports:

# cat 93-sata-lower-power.rules
ACTION=="add", SUBSYSTEM=="scsi_host", KERNEL=="host*", ATTR{proc_name}=="ahci", ATTR{link_power_management_policy}="med_power_with_dipm"

 

[EffrafaxOfWug]

This seems to be the default on my debian laptop at least, although not my servers.

Edit: after a little digging, this setting is governed by a kernel config option CONFIG_SATA_MOBILE_LPM_POLICY