Re: [GD-Windows] Win2K SP2 debugging slowdown?

[Javier A. <ja...@py...>]

If only it were that easy. :)

The situation happens when the game is run under the debugger, using the
debug runtime or not doesn't make a difference. The slowdown magnitude is
huge, about is a few seconds (5-7) versus a couple tenths of a second so I
have ruled out cache, fragmentation and similar issues.

Besides, why does it happen only after installing the Win2K Service Pack 2?
I guess it has something to do with additional security features of the SP2
for processes that run under a debugger, but that's just my own elaboration,
and still leaves me with no idea what triggers the slowdown and how to fix
it.

The hardware configuration doesn't matter, since it's happened everywhere
from 2-year-old P3-450's to brand-new 1.4GHz AMDs, 256 or 512Mb RAM. Heh all
machines have NVidia cards but I really doubt that has anything to do, since
the slowdown happens in areas with zero D3D interaction - sound and massive
memory deallocations so far.

Javier Arevalo
Pyro Studios

----- Original Message -----
From: "Tom Forsyth" <to...@mu...>
To: "GDWindows" <gam...@li...>
Sent: Wednesday, October 03, 2001 1:47 PM
Subject: RE: [GD-Windows] Win2K SP2 debugging slowdown?


> Sounds like the debug runtime is checking every freed block to make sure
you
> haven't scribbled off the ends. When you allocate stuff, it pads the start
> and end with some special characters. IIRC, it pads 16 bytes off start and
> end with FD. When you call free() or delete() or whatever, it checks that
> the FDs are still there.
>
> I have no idea hy it does this more or less than normal though - maybe
> because your memory is heavily fragmented on those runs, so cleanup is
quite
> messy?
>
> Tom Forsyth - Muckyfoot bloke.
>
> What's he up to now (and can I have a go)?
> http://www.eidosinteractive.com/downloads/search.html?gmid=86
>
> > -----Original Message-----
> > From: Javier Arevalo [mailto:ja...@py...]
> > Sent: 03 October 2001 08:28
> > To: GDWindows
> > Subject: [GD-Windows] Win2K SP2 debugging slowdown?
> >
> >
> > Hi all,
> >
> > We have been tracking a weird situation we have, where on
> > some of our dev.
> > machines our game takes several seconds to shut down. We
> > eventually found
> > out the following:
> >
> > - The game must be running in a debugging session under MSVC
> > (haven't tried
> > other debuggers).
> > - The computer must have Windows 2000 _with_ service pack 2 installed.
> >
> > The slowdown happens during a loop that deletes several
> > thousand dynamic
> > memory blocks. Most of the time, sometimes it doesn't.
> > Similar symptoms also
> > appear in other places, like our streaming music decoding thread.
> >
> > Running MSDEV under VTune we found that, when the slowdown
> > happens, most of
> > the time during that loop is spent inside the operating system, spread
> > half-and-half in two functions: RtlCompareMemoryUlong() and
> > RtlFillMemoryUlong().