Stack Overflow?

[Virtual Patient]

Hi all,

When I booted my pc this morning I got this blue screen error:-
There are no spare stack pages. It may be necessary to increase the settings of 'Min SPs' in System.ini to prevent possible stack faults. There are currently 3SPs allocated.

I immediately backed up my work (assignment due in tomorrow) and then checked out the microsoft site for help. The microsoft site has the recommended action I should take listed - Q149083 - and tells me how to increase my SPs, but always in increments of 4.
Why does mine have 3?
Is that what the problem is?
Is there anything I can do to stop whatever device driver is causing the problem?

Shall I just increase to 4 at this stage?

Please will somebody clarify this for me?

VP

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Never be afraid to try something new, remember that amateurs built the Ark, professionals built the Titanic!

[Vernon Frazee]

As that article states, the default is "2". I'd do as it says, start with "4", and try it. If you're still getting the error, increase it to "8", etc. If you get up to say "32" and it's still giving you problems, you need to try and figure out which device driver is causing the problem.

[Virtual Patient]

Thanks Vernon & John,

I am intending to increase the SPs - I'll do it later today.

I was just hoping that if I could track down the culprit I could avoid the situation arising again!

If the multiples of 4 are so important, why is mine 3? confusing.....

VP

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Never be afraid to try something new, remember that amateurs built the Ark, professionals built the Titanic!

[Vernon Frazee]

> If the multiples of 4 are so important, why is mine 3? confusing.....

If the multiples of 4 are so important, why is Microsoft's default "2"?

<-shrug-> http://discussions.virtualdr.com/smile.gif

[Kleinkramer]

From MS:

CAUSE
This behavior can occur when Windows encounters an internal overflow of the stacks that are used by 32-bit Windows-based device drivers. Please note that this is not related to the "Stacks=" line in the Config.sys file, which is used for 16-bit MS-DOS-based device drivers.

Stack overflow conditions are indicative of errors in the device driver. Device drivers are allocated 4 kilobytes (KB), or one page, of space to be used as a stack. If the device driver uses more than 4 KB of memory, a stack overflow condition occurs.

Windows sets aside a number of extra memory pages, or spare stack pages, to be used temporarily so that your computer does not stop responding (hang) due to a stack overflow condition. When the stack overflow condition has passed, Windows reclaims the temporary page. The default number of spare stack pages is two.

If Windows detects that it has run out of spare stack pages, you receive the error message that is mentioned in the "Symptoms" section of this article. Windows continues to operate correctly unless a device driver encounters a stack overflow condition when there are no free spare stack pages.

RESOLUTION
To resolve this behavior, add the following line to the [386Enh] section of the System.ini file, and then restart your computer:

MinSPs=4
If the behavior continues to occur, increase the number of spare stack pages in increments of 4 (for example, 8, 12, 16).

NOTE : Each spare stack page requires 4 KB of memory.

To edit the System.ini file for Windows 95, 98 and 98se:
Click Start , click Run , type sysedit in the Open box, and then click OK .


Click System.ini on the Window menu.

In the [386Enh] section, type the following line:

MinSPs=4
On the File menu, click Exit , and then click Yes to save the changes.

Restart your computer.

[BIG JOHN]

Hi VP, I got the same error about a week ago so I increased mine from 3 to 4 & it resolved the problem. BJ http://discussions.virtualdr.com/biggrin.gif

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"Cause after all, we are just here to help."
BIG JOHN
Virtual Doctor Support Forums Administrator.
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[This message has been edited by BIG JOHN (edited 05-12-2002).]

[Virtual Patient]

Hi chaps,

Thanks for the input.

Perhaps the '3' is just microsofts default 2 and a new one that was created to avoid the stack overflow causing the computer to hang.

thaks again.

VP

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Never be afraid to try something new, remember that amateurs built the Ark, professionals built the Titanic!

[Train]

I have seen 4, 5, and 6.
Now 3 has shown up.

Sounds like multiple programers at work and they all goofed. My 2¢

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SMILE
and post back
[ Book mark this post to find it again]

[This message has been edited by Train (edited 05-12-2002).]

[Ridgerunr]

I got that error right after i installed cable. When i went to [386Enh],it had "no" entry for stack pages(Win98FE).

I set it for 8 and have had no problems since... http://discussions.virtualdr.com/smile.gif

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Badges? We don'need no Steenkin'badges!!

[Virtual Patient]

Funny you should mention cable - I had it installed last week!

VP

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Never be afraid to try something new, remember that amateurs built the Ark, professionals built the Titanic!

[WhitPhil]

Here's the interpretation from SteveYandl of PC911. And the more you see these errors reported, the more this makes sense. Note the distinction between Stack Pages and Spare Stacks.

"The message indicates that there are currently nnn SPs (Stack Pages) assigned, 2 of which are the default Spare Stacks (if there is NOT already a MinSPs entry).
In order to stop the overflow, we need to increase the number of Spares by 4. The MinSPs= setting determines the number of SPARE stack pages that Windows keeps to loan out to drivers that end up using more than the one they are each allocated.
A stack is a reserved piece of memory. When drivers are fired up, they are given a 4k page of memory to use as a kind of "scratch pad" to do certain operations. This is a stack page. Some drivers end up needing a bit more than one page so Windows, by default, keeps two pages to loan out. The pages kept for loan are known as MinSPs."

[Virtual Patient]

Hi WhitPhil,

That is a little easier to understand - it must be connected to this cable broadband modem thingy I just had installed - nothing else has been changed recently.
thank you
VP

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Never be afraid to try something new, remember that amateurs built the Ark, professionals built the Titanic!