[TRACKING] Test results for standby battery use of Expansion Cards

[anarcat]

@lhl

BTW, for shutting off USB here’s a thread w/ a script that another user built that may work for shutting off USB devices on suspension: [Guide] Automatically disable USB devices for battery savings

Thanks, I hadn’t seen that thread (so many threads!). I guess that won’t work for the SSD card since that would crash the filesystem (assuming you can’t unmount…) But still worth a shot.

@lhl

Sadly, I don’t think this will work for the USB-A ports, as they don’t show up in lsusb at all afaict. I believe that there’s probably something going on with those plugged in that are keeping the TB4 active when it shouldn’t be or something.

@Nils had the same thought in:

@Nils

In a way that makes sense if indeed something in the cards prevents something internal on the motherboard to power down properly.The motherboard component is probably supposed to be on whenever the system is on (also when it’s idle), so the difference only really shows when suspended (with deep or s2idle).

It’s really too bad because fixing USB-A is my primary objective here… If i can’t turn off those cards, it means I need to swap them in and out all the time, which makes me wonder what the spec is for those expansion ports, in terms “how many times can i put things in and out until it breaks apart”… I bet it’s not as good as we might like!

@lhl

@nrp mentioned that the Framework Chromebook was able to pass Google’s battery requirements of 14 days of standby and that they learned a lot about Intel’s [Burnside Bridge TB4] re-timers and that this improved behavior is being backported as a firmware update.

This is what is so frustrating here; it looks like the Framework team did figure out a lot of that stuff, but it’s being kept somewhat secret or at least in limited distribution (e.g. to the Chromebook version).

Is the firmware update you’re refering to the DisplayPort beta or is it at the system level?

@lhl

14 days == 336 hours. If it was able to pass that test, on a 55Wh battery, that means that the Framework Chromebook was able to average <163 mW of power drain while in suspend.

I’m not that far from this metric in my tests: with everything turned off (well, with USB-C cards, actually, turns out that helps, weirdly), i’m at 0.23W or 230mW… So close! It’s 10 days, which, for my use case, is pretty good… The problem is the second I add anything on there (and especially USB-A, which I use on a daily basis), it crashes down to 3 days (or explodes to 1W+ depending on your perspective)…

@lhl

(I’m also really interested in whether an updated firmware could really get the Framework to >10h of active usage - that would be <5.5W avg under whatever Google defines as “common tasks”).

I bet it could. I can actually get > 10h by tweaking stuff a bit and holding my breath while powerstat runs. My original power tests gave me 2.5W idle (no cards, again), and I’d typically see 6-9W usage under moderate load (includes playing music, for example).

But start doing anything though, and things go sort of bonkers… I haven’t tested playing videos with, say, a simple player like mpv, but playing videos in Youtube already jumps you past 9W easily. Playing music in a web player like Navidrome threw me up to 12W… So yeah, tricky stuff, power management: you need to manage the entire stack otherwise you leak everything like a sieve everywhere.

Kind of fascinating…