Surface is in a class of devices
that makes use of Modern Standby
to give you instant sleep and instant resume
while using far less power than the traditional S3 sleep,
found and most PCs.
Today I'll walk you through how to generate Sleep Study and Energy Reports
to help pinpoint the cause of power consumption
that may be draining your Surface more than usual while it's in sleep.
A high power consumption while in sleep
means that the device is being interrupted from its lowest power state
Drips, more than it should.
If you are the administrator
you'll want to root cause devices that are experiencing this behavior.
Let me show you how.
Here, I'm remoting into the device
of a user that is complaining that his device is losing power overnight.
So the first thing is to
Start with: powercfg/sleepstudy
And that will give me a report
showing the power consumption while in sleep for the last few sessions.
I'll also run a: powercfg/energy
report, that will give me optimization tips for this device
Now that the reports are ready
I'm going to copy these reports to my device
so that I can look at them in detail.
Let's start by examining the Sleep Study report
to find the active components during Modern Standby
It all starts with this graph.
You'll see multiple colors and multiple styles of lines.
You'll see dotted lines for when the device is charging.
You'll see solid lines for when the device is discharging.
And then you'll see colors.
You'll see grey for an active scenario when the device is on
green for low system activity
orange for moderate system activity
and red for high system activity
In this case we see lots of red
Which is not what we expect.
So let's look further.
Down here you'll see a table
that describes every Modern Standby session lasting more than 10 minutes.
You'll see the energy change, the duration
and the amount of time that it was in the lowest power state, drips.
Ideally, each session should be in drips
for about 95% of the time.
So I would like to see a power consumption 7 to 10 times lower
then the one shown in this graph.
Looking at the latest sessions
I can immediately see session 8
being in drips for only 31% of the time
and consuming about 5% of the battery in only one hour.
In session 9
it also shows me a higher than usual power consumption
with the device being in drips for only 81% of the time
and consuming 1% of the battery in only 23 minutes
Clicking each of the sessions
will take me to a more detailed view.
Drilling into session 8
I can see that Windows update was responsible for most of the additional power consumption
This is something you would have planned
so there is no reason for concern here.
Now in session 9, I see two things
One of them is the BI.
That is the background infrastructure containing universal apps and system components
And the second one is Wi-Fi
That is consuming a lot more power than expected
and this is a concern to me.
Let's find out what's happening.
If I switch to the energy report I can immediately see the issue
There is a red line pinpointing
that the Wi-Fi is set to maximum performance while on battery.
There's no way to change this in the UI
and yet it's somehow been changed.
In fact, most power issues that we see on Surface devices
come from administrators applying settings that are not meant for modern standby devices.
So to fix this issue
I reverted the Wi-Fi power policy back to the default.
One day later, I rerun the Sleep Study report
and see a very big difference.
The slope is less steep
and instead of red, now it is mostly orange and green.
If you look at the table below you'll see the same
You'll see the table itself
is mostly orange and green which is good.
What I do see though
is that session 17 lasted for 16 hours and 18 minutes.
Surface devices should automatically go into hibernation
after 2 to 4 hours of sleep.
This usually means that the device was reimaged
and that the hibernation power policy was not applied.
Let me show you how to do that.
If you open to group policy edits
and change the sleep settings
you can go to 'Specify the system hibernate timeouts (on battery)'.
and you can choose any value.
Remember, this is said and seconds
so 7,200 seconds would be the default
I hope today's demo bench
helps you troubleshoot unexpected power consumptions
while your Surface devices are in sleep
Keep checking demo bench
for the latest information on Surface management and design.
Thanks for watching.
Microsoft Mechanics
www.microsoft.com/mechanics