driver verifier low resources simulation

NTDEV
1

Hi everybody,

I like to test my driver with the “low resources simulation” option set but
I am fed up to have to wait 7 minutes every time before it kicks in. Is
there an option to have it start any sooner?

ps: today is a beautiful day in Luxembourg and I have a new motorbike to
ride and these 7-minutes intervals drive me mad!

thanks!

–
Marco [www.neovalens.com]

2

Why 7 minutes? Is that how long it takes for your machine to reboot?
Any change in driver verifier settings require a reboot, there is no way
to immediately enforce the settings to update.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Marco Peretti
Sent: Friday, March 18, 2005 7:13 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] driver verifier low resources simulation

Hi everybody,

I like to test my driver with the “low resources simulation” option set
but
I am fed up to have to wait 7 minutes every time before it kicks in. Is
there an option to have it start any sooner?

ps: today is a beautiful day in Luxembourg and I have a new motorbike to

ride and these 7-minutes intervals drive me mad!

thanks!

–
Marco [www.neovalens.com]

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

3

xxxxx@lists.osr.com wrote on 03/18/2005 04:03:49 PM:

Why 7 minutes? Is that how long it takes for your machine to reboot?
Any change in driver verifier settings require a reboot, there is no way
to immediately enforce the settings to update.

I think Marco was referring to the fact that “low resources” isn’t
simulated until the driver has been up and running for some time (7
minutes). That, from what I was told at the 2003 driver devcon, is so that
the driver can get up and running without having to suffer low resources
during the actual startup (which should rarely be the case).

–
Mats

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Marco Peretti
Sent: Friday, March 18, 2005 7:13 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] driver verifier low resources simulation

Hi everybody,

I like to test my driver with the “low resources simulation” option set
but
I am fed up to have to wait 7 minutes every time before it kicks in. Is
there an option to have it start any sooner?

ps: today is a beautiful day in Luxembourg and I have a new motorbike to

ride and these 7-minutes intervals drive me mad!

thanks!

–
Marco [www.neovalens.com]

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

Questions? First check the Kernel Driver FAQ at http://www.
osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: unknown lmsubst tag argument:
‘’
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ForwardSourceID:NT0000F0AE

4

Doron,
In an article by Mark Russinovich I once read this:

“Thus, beginning 7 minutes after the system boots-which is enough time to
get past the critical initialization period in which a low-memory condition
might prevent a device driver from loading- the Verifier starts randomly
failing allocation calls for device drivers it is verifying.”
http://www.windowsitpro.com/Windows/Articles/ArticleID/7206/pg/2/2.html

This is what Marco is reffering to, but I don’t believe this behavior is
configurable :).

Shahar

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Doron Holan
Sent: Friday, March 18, 2005 6:04 PM
To: Windows System Software Devs Interest List
Subject: RE: [ntdev] driver verifier low resources simulation

Why 7 minutes? Is that how long it takes for your machine to reboot?
Any change in driver verifier settings require a reboot, there is no way to
immediately enforce the settings to update.

d

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Marco Peretti
Sent: Friday, March 18, 2005 7:13 AM
To: Windows System Software Devs Interest List
Subject: [ntdev] driver verifier low resources simulation

Hi everybody,

I like to test my driver with the “low resources simulation” option set but
I am fed up to have to wait 7 minutes every time before it kicks in. Is
there an option to have it start any sooner?

ps: today is a beautiful day in Luxembourg and I have a new motorbike to

ride and these 7-minutes intervals drive me mad!

thanks!

–
Marco [www.neovalens.com]

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

Questions? First check the Kernel Driver FAQ at
http://www.osronline.com/article.cfm?id=256

You are currently subscribed to ntdev as: unknown lmsubst tag argument: ‘’
To unsubscribe send a blank email to xxxxx@lists.osr.com

5

“Mats PETERSSON” wrote in message
news:xxxxx@ntdev…
>
> I think Marco was referring to the fact that “low resources” isn’t
> simulated until the driver has been up and running for some time (7
> minutes). That, from what I was told at the 2003 driver devcon, is so that
> the driver can get up and running without having to suffer low resources
> during the actual startup (which should rarely be the case).
>

that is indeed what I meant: my machine boots pretty fast and then I have to
wait for
7 minutes for driver verifier to begin failing memory allocations.

I just wanted to know if there is an option to change the default delay.

I find the “low resources simulation” option usueful to improve the error
handling
and it has helped me more than once to catch a few bugs.

cheers,

Marco

6

If it’s a 32bit driver, run Verifier inside a virtual machine. Set all the
options, leave it running for 7 minutes then take a snapshot that you can
restore to within seconds.

Regards,

Daniel Terhell
Resplendence Software Projects Sp
xxxxx@resplendence.com
http://www.resplendence.com

“Marco Peretti” wrote in message news:xxxxx@ntdev…
> Hi everybody,
>
> I like to test my driver with the “low resources simulation” option set
> but I am fed up to have to wait 7 minutes every time before it kicks in.
> Is there an option to have it start any sooner?
>
> ps: today is a beautiful day in Luxembourg and I have a new motorbike to
> ride and these 7-minutes intervals drive me mad!
>
> thanks!
>
> –
> Marco [www.neovalens.com]
> –
>
>
>

7

Silly of me, this is not going to work as you will not be able to update a
running driver. Nonetheless you can your boot time.

/Daniel

“Daniel Terhell” wrote in message
news:xxxxx@ntdev…
> If it’s a 32bit driver, run Verifier inside a virtual machine. Set all the
> options, leave it running for 7 minutes then take a snapshot that you can
> restore to within seconds.
>
> Regards,
>
> Daniel Terhell
> Resplendence Software Projects Sp
> xxxxx@resplendence.com
> http://www.resplendence.com
>
>
>
>
> “Marco Peretti” wrote in message
> news:xxxxx@ntdev…
>> Hi everybody,
>>
>> I like to test my driver with the “low resources simulation” option set
>> but I am fed up to have to wait 7 minutes every time before it kicks in.
>> Is there an option to have it start any sooner?
>>
>> ps: today is a beautiful day in Luxembourg and I have a new motorbike to
>> ride and these 7-minutes intervals drive me mad!
>>
>> thanks!
>>
>> –
>> Marco [www.neovalens.com]
>> –
>>
>>
>>
>
>
>

8

“Daniel Terhell” wrote in message
news:xxxxx@ntdev…

>>If it’s a 32bit driver, run Verifier inside a virtual machine. Set all the
>>options, leave it running for 7 minutes then take a snapshot that you can
>>restore to within seconds.

> Silly of me, this is not going to work as you will not be able to update a
> running driver. Nonetheless you can your boot time.
>

Hi Daniel

I like the idea!. I often test with my driver in manual start so I can
actually replace it anytime. By the way, the 7-minutes delay is related to
system uptime, not specific to a driver.

thanks,

Marco

9

Unlike other tests, this one is not supposed to find issues as fast as other
tests do.
Test in low resources simulation mode by the definition should be
time-consuming in order to be relevant - ideally it should take days or
weeks in automated mode to ensure driver will stably work in production
environment, so I doubt 7 minutes is an issue at all.

Andrey.