Critical Shutdown?

I’m trying to understand the shutdown process due to high CPU
temperature, but can’t find any documentation or description of it.

In WinDbg, I’ve found the !tz and !tzinfo commands to dump the ACPI
thermal critical trip point and so on. But I can’t find any
documentation that describes the “thermal zone information structure”
(such as how it gets its information, and so on).

I did come across the sentence “Note that the power policy manager has a
hard-coded policy to initiate a CriticalShutdownOff whenever any thermal
zone indicates a critical thermal condition.”

That then begs the question, “What is a CriticalShutdownOff?” I
couldn’t find any documentation or mention of that (not even with
Google) except for that one page. Even “CriticalShutdown” only gives
one hit in MSDN.

Can anyone explain a Windows critical shutdown or point me to some
documentation? For example, how it differs from a normal shutdown, what
would trigger a critical shutdown, any possible callback registration,
etc.

Thanks in advance!

Critical Shutdown?I don’t have any answers, but there may be something related to this: at least back in Windows 2000, hitting the power button on a desktop PC would initiate an “emergency shutdown” - a quick flush of write buffers on the disk and an immediate ACPI halt. Maybe you can find some relevant information on that.
“Taed Wynnell” wrote in message news:xxxxx@ntdev…
I’m trying to understand the shutdown process due to high CPU temperature, but can’t find any documentation or description of it.

In WinDbg, I’ve found the !tz and !tzinfo commands to dump the ACPI thermal critical trip point and so on. But I can’t find any documentation that describes the “thermal zone information structure” (such as how it gets its information, and so on).

I did come across the sentence “Note that the power policy manager has a hard-coded policy to initiate a CriticalShutdownOff whenever any thermal zone indicates a critical thermal condition.”

That then begs the question, “What is a CriticalShutdownOff?” I couldn’t find any documentation or mention of that (not even with Google) except for that one page. Even “CriticalShutdown” only gives one hit in MSDN.

Can anyone explain a Windows critical shutdown or point me to some documentation? For example, how it differs from a normal shutdown, what would trigger a critical shutdown, any possible callback registration, etc.

Thanks in advance!

Hitting the power button should initiate a normal system shutdown, perhaps you are confusing this with a UPS button. I asked the power folks and here is the answer I got

It’s a kernel-level only shutdown. We skip apps/services (because we can’t risk the time) and only do basic low-level shutdown operations (flushing anything cached in RAM to disk, making sure the file system is consistent, etc.) – basically everything we need to do to make sure the system remains consistent and you can cleanly boot again later.

Usermode apps can definitely lose data, but the rationale is that this is a better situation than bricking the entire system.

So to answer the OP’s question, there is nothing you can register for that will tell you that a critical shutdown is occurring. That would introduce new timings and delays that (IMHO) are not needed in this scenario

d

From: xxxxx@lists.osr.com [mailto:xxxxx@lists.osr.com] On Behalf Of comrade
Sent: Thursday, July 24, 2008 7:11 AM
To: Windows System Software Devs Interest List
Subject: Re:[ntdev] Critical Shutdown?

I don’t have any answers, but there may be something related to this: at least back in Windows 2000, hitting the power button on a desktop PC would initiate an “emergency shutdown” - a quick flush of write buffers on the disk and an immediate ACPI halt. Maybe you can find some relevant information on that.
“Taed Wynnell” > wrote in message news:xxxxx@ntdev…

I’m trying to understand the shutdown process due to high CPU temperature, but can’t find any documentation or description of it.

In WinDbg, I’ve found the !tz and !tzinfo commands to dump the ACPI thermal critical trip point and so on. But I can’t find any documentation that describes the “thermal zone information structure” (such as how it gets its information, and so on).

I did come across the sentence “Note that the power policy manager has a hard-coded policy to initiate a CriticalShutdownOff whenever any thermal zone indicates a critical thermal condition.”

That then begs the question, “What is a CriticalShutdownOff?” I couldn’t find any documentation or mention of that (not even with Google) except for that one page. Even “CriticalShutdown” only gives one hit in MSDN.

Can anyone explain a Windows critical shutdown or point me to some documentation? For example, how it differs from a normal shutdown, what would trigger a critical shutdown, any possible callback registration, etc.

Thanks in advance!


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Good thinking, but it didn’t work out. I just looked at that – I think
you’re talking about the Display Control Panel | Power Options | Advanced |
“When I press the power button” … “Shutdown”. But that just seems to do a
clean shutdown, not a critical one. (Critical shutdowns are semi-immediate;
I see shutdown handlers get called, but other than that, they are basically
instantaneous and show up as “abnormal shutdowns” in the event log.)

Thanks anyway!

“comrade” wrote in message news:xxxxx@ntdev…
Critical Shutdown?I don’t have any answers, but there may be something
related to this: at least back in Windows 2000, hitting the power button on
a desktop PC would initiate an “emergency shutdown” - a quick flush of write
buffers on the disk and an immediate ACPI halt. Maybe you can find some
relevant information on that.

“Taed Wynnell” wrote in message
news:xxxxx@ntdev…
I’m trying to understand the shutdown process due to high CPU temperature,
but can’t find any documentation or description of it.

In WinDbg, I’ve found the !tz and !tzinfo commands to dump the ACPI
thermal critical trip point and so on. But I can’t find any documentation
that describes the “thermal zone information structure” (such as how it gets
its information, and so on).

I did come across the sentence “Note that the power policy manager has a
hard-coded policy to initiate a CriticalShutdownOff whenever any thermal
zone indicates a critical thermal condition.”

That then begs the question, “What is a CriticalShutdownOff?” I couldn’t
find any documentation or mention of that (not even with Google) except for
that one page. Even “CriticalShutdown” only gives one hit in MSDN.

Can anyone explain a Windows critical shutdown or point me to some
documentation? For example, how it differs from a normal shutdown, what
would trigger a critical shutdown, any possible callback registration, etc.

Thanks in advance!

I believe high temperature shutdowns may be triggered by activating SMM mode (http://en.wikipedia.org/wiki/System_Management_Mode) code. I am not 100% sure, but this would be appropriate and would explain why you see no trace of the Critical Shutdown.

-A Frolenkov.

That’s exactly the information that I’ve been looking for! Thank you so
much! (I’ve had a Microsoft support case open for nearly 2 months trying to
get that information…)

The follow-on question is: What, other than an ACPI thermal critical trip
point, would cause a Critical Shutdown?

The quick background on my issue is that we’ve seen a few systems do this
sudden Critical Shutdown in the field, and we know it’s not
temperature-related since we’ve been monitoring the temperature and it never
gets anywhere near the 95C trip point. So, we want to understand why we see
this occasional shutdown. We’ve seen it on about 5 machines, but only once
per machine, so it’s not reproducible or reoccurring, and so doesn’t seem to
be environmental or some problem with the machines.

“Doron Holan” wrote in message
news:xxxxx@ntdev…
Hitting the power button should initiate a normal system shutdown, perhaps
you are confusing this with a UPS button. I asked the power folks and here
is the answer I got

It’s a kernel-level only shutdown. We skip apps/services (because we can’t
risk the time) and only do basic low-level shutdown operations (flushing
anything cached in RAM to disk, making sure the file system is consistent,
etc.) – basically everything we need to do to make sure the system remains
consistent and you can cleanly boot again later.

Usermode apps can definitely lose data, but the rationale is that this is a
better situation than bricking the entire system.

So to answer the OP’s question, there is nothing you can register for that
will tell you that a critical shutdown is occurring. That would introduce
new timings and delays that (IMHO) are not needed in this scenario

d

From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of comrade
Sent: Thursday, July 24, 2008 7:11 AM
To: Windows System Software Devs Interest List
Subject: Re:[ntdev] Critical Shutdown?

I don’t have any answers, but there may be something related to this: at
least back in Windows 2000, hitting the power button on a desktop PC would
initiate an “emergency shutdown” - a quick flush of write buffers on the
disk and an immediate ACPI halt. Maybe you can find some relevant
information on that.
“Taed Wynnell” > wrote
in message news:xxxxx@ntdev…

I’m trying to understand the shutdown process due to high CPU temperature,
but can’t find any documentation or description of it.

In WinDbg, I’ve found the !tz and !tzinfo commands to dump the ACPI thermal
critical trip point and so on. But I can’t find any documentation that
describes the “thermal zone information structure” (such as how it gets its
information, and so on).

I did come across the sentence “Note that the power policy manager has a
hard-coded policy to initiate a CriticalShutdownOff whenever any thermal
zone indicates a critical thermal condition.”

That then begs the question, “What is a CriticalShutdownOff?” I couldn’t
find any documentation or mention of that (not even with Google) except for
that one page. Even “CriticalShutdown” only gives one hit in MSDN.

Can anyone explain a Windows critical shutdown or point me to some
documentation? For example, how it differs from a normal shutdown, what
would trigger a critical shutdown, any possible callback registration, etc.

Thanks in advance!


NTDEV is sponsored by OSR

For our schedule of WDF, WDM, debugging and other seminars visit:
http://www.osr.com/seminars

To unsubscribe, visit the List Server section of OSR Online at
http://www.osronline.com/page.cfm?name=ListServer

> The follow-on question is: What, other than an ACPI thermal

critical trip point, would cause a Critical Shutdown?

I know if you type “restart” in an ems console, the system goes down much
more rapidly than if you do shutdown from the gui.

Jan