C# app lockup - debugging / tools

I have a C# app that's locking up the handheld, forcing a reboot. It works
fine for hours, then suddenly locks up. If I run the app in the debugger,
when the lockup on the handheld occurs, if I "break all", the debugger locks
up as well, until I physically disconnect the device from the host. The
handheld is running Windows Mobile 5.2, and I'm debugging via VS 2008 and AS
4.5.

The lockup occurs when interacting with a control I wrote that allows the
user to drag a foreground image over a background image. It responds to
mouse up/down and paint events, and invokes an application-specified callback
function passing the X,Y position of the foreground image.

I suspect there is some sort of resource leakage going on, but I'm not
familiar with tools or techniques for detecting such things on a handheld.
Can anyone point me in the right direction? Thanks,

-Dan

Chris
Thu Jul 10 16:37:20 CDT 2008

Do a search for "remote performance monitor"

-Chris

"Dan Ritchie" <DanRitchie@discussions.microsoft.com> wrote in message
news:E9EA2BCF-50E2-4962-9726-AC592AA03EF1@microsoft.com...
>I have a C# app that's locking up the handheld, forcing a reboot. It works
> fine for hours, then suddenly locks up. If I run the app in the debugger,
> when the lockup on the handheld occurs, if I "break all", the debugger
> locks
> up as well, until I physically disconnect the device from the host. The
> handheld is running Windows Mobile 5.2, and I'm debugging via VS 2008 and
> AS
> 4.5.
>
> The lockup occurs when interacting with a control I wrote that allows the
> user to drag a foreground image over a background image. It responds to
> mouse up/down and paint events, and invokes an application-specified
> callback
> function passing the X,Y position of the foreground image.
>
> I suspect there is some sort of resource leakage going on, but I'm not
> familiar with tools or techniques for detecting such things on a handheld.
> Can anyone point me in the right direction? Thanks,
>
> -Dan

DanRitchie
Thu Jul 17 14:00:04 CDT 2008

Thanks for the suggestion. Using RPM I don't see any evidence of memory
leakage. I wonder if you know of a way to monitor CPU usage on the device
(RPM doesn't seem to show it). It would be good to see if there is an
infinite loop going on, and if so what process it occurs in.

This is an interesting problem. Each occurrence has taken me hours to
reproduce. Result is the system locks up and is totally unresponsive, even
the system time stops updating. The debugger does not detect any RT
exceptions or anything.

"Chris Tacke, MVP" wrote:

> Do a search for "remote performance monitor"
>
> -Chris
>
> "Dan Ritchie" <DanRitchie@discussions.microsoft.com> wrote in message
> news:E9EA2BCF-50E2-4962-9726-AC592AA03EF1@microsoft.com...
> >I have a C# app that's locking up the handheld, forcing a reboot. It works
> > fine for hours, then suddenly locks up. If I run the app in the debugger,
> > when the lockup on the handheld occurs, if I "break all", the debugger
> > locks
> > up as well, until I physically disconnect the device from the host. The
> > handheld is running Windows Mobile 5.2, and I'm debugging via VS 2008 and
> > AS
> > 4.5.
> >
> > The lockup occurs when interacting with a control I wrote that allows the
> > user to drag a foreground image over a background image. It responds to
> > mouse up/down and paint events, and invokes an application-specified
> > callback
> > function passing the X,Y position of the foreground image.
> >
> > I suspect there is some sort of resource leakage going on, but I'm not
> > familiar with tools or techniques for detecting such things on a handheld.
> > Can anyone point me in the right direction? Thanks,
> >
> > -Dan
>

Chris
Thu Jul 17 14:22:20 CDT 2008

ARM processors don't have an easy way to detect processor load like x86, so
you won't find any way on the device (or in CE for that matter) to get that
info. You could use Kernel Tracker to look at what's getting scheduled and
see if anything really ugly jumps out at you. Anything eating up quantum
will show up really fast there.


--

Chris Tacke, Embedded MVP
OpenNETCF Consulting
Giving back to the embedded community
http://community.OpenNETCF.com

"Dan Ritchie" <DanRitchie@discussions.microsoft.com> wrote in message
news:9BDF6285-6E31-41FE-84CF-0178670B0CF7@microsoft.com...
> Thanks for the suggestion. Using RPM I don't see any evidence of memory
> leakage. I wonder if you know of a way to monitor CPU usage on the device
> (RPM doesn't seem to show it). It would be good to see if there is an
> infinite loop going on, and if so what process it occurs in.
>
> This is an interesting problem. Each occurrence has taken me hours to
> reproduce. Result is the system locks up and is totally unresponsive,
> even
> the system time stops updating. The debugger does not detect any RT
> exceptions or anything.
>
> "Chris Tacke, MVP" wrote:
>
>> Do a search for "remote performance monitor"
>>
>> -Chris
>>
>> "Dan Ritchie" <DanRitchie@discussions.microsoft.com> wrote in message
>> news:E9EA2BCF-50E2-4962-9726-AC592AA03EF1@microsoft.com...
>> >I have a C# app that's locking up the handheld, forcing a reboot. It
>> >works
>> > fine for hours, then suddenly locks up. If I run the app in the
>> > debugger,
>> > when the lockup on the handheld occurs, if I "break all", the debugger
>> > locks
>> > up as well, until I physically disconnect the device from the host.
>> > The
>> > handheld is running Windows Mobile 5.2, and I'm debugging via VS 2008
>> > and
>> > AS
>> > 4.5.
>> >
>> > The lockup occurs when interacting with a control I wrote that allows
>> > the
>> > user to drag a foreground image over a background image. It responds
>> > to
>> > mouse up/down and paint events, and invokes an application-specified
>> > callback
>> > function passing the X,Y position of the foreground image.
>> >
>> > I suspect there is some sort of resource leakage going on, but I'm not
>> > familiar with tools or techniques for detecting such things on a
>> > handheld.
>> > Can anyone point me in the right direction? Thanks,
>> >
>> > -Dan
>>