First exception is very slow...

[Robert Gravereaux]

I've noticed that the first exception thrown/caught by an app running in
debug is very slow - it takes perhaps 7 or 8 seconds on my P4 machine. I've
noticed this on several different machines running the development
environment.

To replicate, create a new c# windows app, add a button, and hook it to the
following code:
private void btnException_Click(object sender, System.EventArgs e)
{
try
{
throw new ApplicationException("Exception!!!");
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

Run the app in debug (F5), click on the button, and wait about 5-10 sec. for
the message box to appear. Clicking a second time causes the message box to
appear immediately.

Can anyone tell me what's causing this, and is there a solution/workaround?

Thanks.

--
Rob Gravereaux
Principal Developer
Glen Road Systems, Inc.
Ro********************@grsinc.com
http://www.grsinc.com

[Nicholas Paldino [.NET/C# MVP]]

Robert,

Catching exceptions is always a more expensive operation. The runtime
might hold of until a first occurance in order to save some time. The only
way I can think of to get around this would be to create a new thread,
throwing and catching an exception on that thread, and then exiting.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

I've noticed that the first exception thrown/caught by an app running in
debug is very slow - it takes perhaps 7 or 8 seconds on my P4 machine. I've noticed this on several different machines running the development
environment.

To replicate, create a new c# windows app, add a button, and hook it to the following code:
private void btnException_Click(object sender, System.EventArgs e)
{
try
{
throw new ApplicationException("Exception!!!");
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

Run the app in debug (F5), click on the button, and wait about 5-10 sec. for the message box to appear. Clicking a second time causes the message box to appear immediately.

Can anyone tell me what's causing this, and is there a solution/workaround?
Thanks.

--
Rob Gravereaux
Principal Developer
Glen Road Systems, Inc.
Ro********************@grsinc.com
http://www.grsinc.com

[Robert Gravereaux]

Thanks for the reply.

It only happens when running apps in debug in the IDE. It does not occur if
I run the compiled executable, so I don't think I'd want to add additional
code if possible.

Is this behaviour affected by any of the settings of the debugger?

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in
message news:%2****************@TK2MSFTNGP09.phx.gbl...

Robert,

Catching exceptions is always a more expensive operation. The runtime
might hold of until a first occurance in order to save some time. The only way I can think of to get around this would be to create a new thread,
throwing and catching an exception on that thread, and then exiting.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

I've noticed that the first exception thrown/caught by an app running in
debug is very slow - it takes perhaps 7 or 8 seconds on my P4 machine.

I've

noticed this on several different machines running the development
environment.

To replicate, create a new c# windows app, add a button, and hook it to

the

following code:
private void btnException_Click(object sender, System.EventArgs e)
{
try
{
throw new ApplicationException("Exception!!!");
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

Run the app in debug (F5), click on the button, and wait about 5-10 sec.

for

the message box to appear. Clicking a second time causes the message box

to

appear immediately.

Can anyone tell me what's causing this, and is there a

solution/workaround?

Thanks.

--
Rob Gravereaux
Principal Developer
Glen Road Systems, Inc.
Ro********************@grsinc.com
http://www.grsinc.com

[Nicholas Paldino [.NET/C# MVP]]

Robert,

Of course! The fact that it is being debugged in the first place
changes a lot. You have one process basically hooking into another process
as it is executing code. I can't imagine that there ^wouldn't^ be any
overhead involved in this process, as well as initialization and tear-down
code.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

Thanks for the reply.

It only happens when running apps in debug in the IDE. It does not occur if I run the compiled executable, so I don't think I'd want to add additional
code if possible.

Is this behaviour affected by any of the settings of the debugger?

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in message news:%2****************@TK2MSFTNGP09.phx.gbl...

Robert,

Catching exceptions is always a more expensive operation. The runtime might hold of until a first occurance in order to save some time. The

only

way I can think of to get around this would be to create a new thread,
throwing and catching an exception on that thread, and then exiting.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

I've noticed that the first exception thrown/caught by an app running in debug is very slow - it takes perhaps 7 or 8 seconds on my P4 machine.

I've

noticed this on several different machines running the development
environment.

To replicate, create a new c# windows app, add a button, and hook it

to the

following code:
private void btnException_Click(object sender, System.EventArgs e)
{
try
{
throw new ApplicationException("Exception!!!");
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
}

Run the app in debug (F5), click on the button, and wait about 5-10

sec. for

the message box to appear. Clicking a second time causes the message

box to

appear immediately.

Can anyone tell me what's causing this, and is there a

solution/workaround?

Thanks.

--
Rob Gravereaux
Principal Developer
Glen Road Systems, Inc.
Ro********************@grsinc.com
http://www.grsinc.com

[Robert Gravereaux]

OK, I'll accept that, in general. however 5 - 10 seconds seems excessive,
and for the 5 - 10 seconds I'm waiting nothing appears to be happening, i.e.
no disk activity, no libraries appear to be loading, etc...

For kicks I ran the same code in debug in VS.Net 2002 on the same machine
and I get what I'd expect - the catch block is executed immediately the
first time. So I still think my issue is valid. I guess this is either a
configuration issue in VS.Net 2003 or, dare I say it, a bug.

Can you replicate this behaviour in your environment? I can't believe this
is 'normal' for VS.Net 2003, yet it happens on every install I have.

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in
message news:OI**************@TK2MSFTNGP09.phx.gbl...

Robert,

Of course! The fact that it is being debugged in the first place
changes a lot. You have one process basically hooking into another process as it is executing code. I can't imagine that there ^wouldn't^ be any
overhead involved in this process, as well as initialization and tear-down
code.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

Thanks for the reply.

It only happens when running apps in debug in the IDE. It does not occur if

I run the compiled executable, so I don't think I'd want to add additional

code if possible.

Is this behaviour affected by any of the settings of the debugger?

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote

in

message news:%2****************@TK2MSFTNGP09.phx.gbl...

Robert,

Catching exceptions is always a more expensive operation. The

runtime might hold of until a first occurance in order to save some time. The

only

way I can think of to get around this would be to create a new thread,
throwing and catching an exception on that thread, and then exiting.

Hope this helps.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message news:%2****************@TK2MSFTNGP12.phx.gbl...
> I've noticed that the first exception thrown/caught by an app running in

> debug is very slow - it takes perhaps 7 or 8 seconds on my P4

machine. I've
> noticed this on several different machines running the development
> environment.
>
> To replicate, create a new c# windows app, add a button, and hook it

to the
> following code:
> private void btnException_Click(object sender, System.EventArgs e)
> {
> try
> {
> throw new ApplicationException("Exception!!!");
> }
> catch(Exception ex)
> {
> MessageBox.Show(ex.ToString());
> }
> }
>
> Run the app in debug (F5), click on the button, and wait about 5-10 sec. for
> the message box to appear. Clicking a second time causes the message box to
> appear immediately.
>
> Can anyone tell me what's causing this, and is there a
solution/workaround?
>
> Thanks.
>
> --
> Rob Gravereaux
> Principal Developer
> Glen Road Systems, Inc.
> Ro********************@grsinc.com
> http://www.grsinc.com
>
>

[Nicholas Paldino [.NET/C# MVP]]

Robert,

If you email me a zipped project, I can take a look at it on my machine.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:O7**************@TK2MSFTNGP11.phx.gbl...

OK, I'll accept that, in general. however 5 - 10 seconds seems excessive,
and for the 5 - 10 seconds I'm waiting nothing appears to be happening, i.e. no disk activity, no libraries appear to be loading, etc...

For kicks I ran the same code in debug in VS.Net 2002 on the same machine
and I get what I'd expect - the catch block is executed immediately the
first time. So I still think my issue is valid. I guess this is either a
configuration issue in VS.Net 2003 or, dare I say it, a bug.

Can you replicate this behaviour in your environment? I can't believe this
is 'normal' for VS.Net 2003, yet it happens on every install I have.

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in message news:OI**************@TK2MSFTNGP09.phx.gbl...

Robert,

Of course! The fact that it is being debugged in the first place
changes a lot. You have one process basically hooking into another

process

as it is executing code. I can't imagine that there ^wouldn't^ be any
overhead involved in this process, as well as initialization and tear-down

code.
--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP12.phx.gbl...

Thanks for the reply.

It only happens when running apps in debug in the IDE. It does not occur

if

I run the compiled executable, so I don't think I'd want to add additional code if possible.

Is this behaviour affected by any of the settings of the debugger?

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com>

wrote in

message news:%2****************@TK2MSFTNGP09.phx.gbl...
> Robert,
>
> Catching exceptions is always a more expensive operation. The

runtime

> might hold of until a first occurance in order to save some time.

The only
> way I can think of to get around this would be to create a new thread, > throwing and catching an exception on that thread, and then exiting.
>
> Hope this helps.
>
>
> --
> - Nicholas Paldino [.NET/C# MVP]
> - mv*@spam.guard.caspershouse.com
>
> "Robert Gravereaux" <Ro********************@grsinc.com> wrote in

message > news:%2****************@TK2MSFTNGP12.phx.gbl...
> > I've noticed that the first exception thrown/caught by an app running

in

> > debug is very slow - it takes perhaps 7 or 8 seconds on my P4

machine. > I've
> > noticed this on several different machines running the development
> > environment.
> >
> > To replicate, create a new c# windows app, add a button, and hook

it to

> the
> > following code:
> > private void btnException_Click(object sender, System.EventArgs e)
> > {
> > try
> > {
> > throw new ApplicationException("Exception!!!");
> > }
> > catch(Exception ex)
> > {
> > MessageBox.Show(ex.ToString());
> > }
> > }
> >
> > Run the app in debug (F5), click on the button, and wait about

5-10 sec.

> for
> > the message box to appear. Clicking a second time causes the

message box

> to
> > appear immediately.
> >
> > Can anyone tell me what's causing this, and is there a
> solution/workaround?
> >
> > Thanks.
> >
> > --
> > Rob Gravereaux
> > Principal Developer
> > Glen Road Systems, Inc.
> > Ro********************@grsinc.com
> > http://www.grsinc.com
> >
> >
>
>

[Nicholas Paldino [.NET/C# MVP]]

Robert,

I am getting approximately the same results (3 seconds on the first one,
none on the subsequent calls). I can only guess, but I imagine it has
something to do with the way that the CLR exposes debugging functionality,
and possibly with the way that VS.NET hooks up with the CLR for debugging,
and the possibility of those things changing between .NET 1.0 and .NET 1.1.

However, when running a release version, I do not get this.

Given that the versions we run are debug versions, I can't say I am
extremely concerned. I can ask around why this might happen though, and
post if I find anything.

--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP10.phx.gbl...

Here's a sample app. It's the same code from my first posting, with the
addition of some timing code.

Please run it in debug from the VS.Net 2003 IDE, click the button and wait. On my environments the first exception takes anywhere from 3 to 10 seconds
to be caught. After that it's immediate.

In VS.Net 2002 the first exception is caught immediately.

Let me know what your times are.

Thanks.

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in message news:O8**************@TK2MSFTNGP11.phx.gbl...

Robert,

If you email me a zipped project, I can take a look at it on my machine.

--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:O7**************@TK2MSFTNGP11.phx.gbl...

OK, I'll accept that, in general. however 5 - 10 seconds seems excessive, and for the 5 - 10 seconds I'm waiting nothing appears to be happening,

i.e.

no disk activity, no libraries appear to be loading, etc...

For kicks I ran the same code in debug in VS.Net 2002 on the same machine and I get what I'd expect - the catch block is executed immediately

the first time. So I still think my issue is valid. I guess this is either a configuration issue in VS.Net 2003 or, dare I say it, a bug.

Can you replicate this behaviour in your environment? I can't believe this is 'normal' for VS.Net 2003, yet it happens on every install I have.

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in

message news:OI**************@TK2MSFTNGP09.phx.gbl...
> Robert,
>
> Of course! The fact that it is being debugged in the first

place > changes a lot. You have one process basically hooking into another
process
> as it is executing code. I can't imagine that there ^wouldn't^ be any > overhead involved in this process, as well as initialization and

tear-down

> code.
>
>
> --
> - Nicholas Paldino [.NET/C# MVP]
> - mv*@spam.guard.caspershouse.com
>
> "Robert Gravereaux" <Ro********************@grsinc.com> wrote in message > news:%2****************@TK2MSFTNGP12.phx.gbl...
> > Thanks for the reply.
> >
> > It only happens when running apps in debug in the IDE. It does not

occur

> if
> > I run the compiled executable, so I don't think I'd want to add
additional
> > code if possible.
> >
> > Is this behaviour affected by any of the settings of the debugger?
> >
> > "Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com>

wrote

> in
> > message news:%2****************@TK2MSFTNGP09.phx.gbl...
> > > Robert,
> > >
> > > Catching exceptions is always a more expensive operation. The > runtime
> > > might hold of until a first occurance in order to save some

time. The

> > only
> > > way I can think of to get around this would be to create a new

thread,

> > > throwing and catching an exception on that thread, and then

exiting. > > >
> > > Hope this helps.
> > >
> > >
> > > --
> > > - Nicholas Paldino [.NET/C# MVP]
> > > - mv*@spam.guard.caspershouse.com
> > >
> > > "Robert Gravereaux" <Ro********************@grsinc.com> wrote in
message
> > > news:%2****************@TK2MSFTNGP12.phx.gbl...
> > > > I've noticed that the first exception thrown/caught by an app
running
> in
> > > > debug is very slow - it takes perhaps 7 or 8 seconds on my P4
machine.
> > > I've
> > > > noticed this on several different machines running the development > > > > environment.
> > > >
> > > > To replicate, create a new c# windows app, add a button, and hook

it

> to
> > > the
> > > > following code:
> > > > private void btnException_Click(object sender,

System.EventArgs e) > > > > {
> > > > try
> > > > {
> > > > throw new ApplicationException("Exception!!!");
> > > > }
> > > > catch(Exception ex)
> > > > {
> > > > MessageBox.Show(ex.ToString());
> > > > }
> > > > }
> > > >
> > > > Run the app in debug (F5), click on the button, and wait about

5-10

> sec.
> > > for
> > > > the message box to appear. Clicking a second time causes the

message

> box
> > > to
> > > > appear immediately.
> > > >
> > > > Can anyone tell me what's causing this, and is there a
> > > solution/workaround?
> > > >
> > > > Thanks.
> > > >
> > > > --
> > > > Rob Gravereaux
> > > > Principal Developer
> > > > Glen Road Systems, Inc.
> > > > Ro********************@grsinc.com
> > > > http://www.grsinc.com
> > > >
> > > >
> > >
> > >
> >
> >
>
>

[Robert Gravereaux]

I'd appreciate anything you can find out.

Thanks for the effort.
"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote in
message news:ug**************@tk2msftngp13.phx.gbl...

Robert,

I am getting approximately the same results (3 seconds on the first one, none on the subsequent calls). I can only guess, but I imagine it has
something to do with the way that the CLR exposes debugging functionality,
and possibly with the way that VS.NET hooks up with the CLR for debugging,
and the possibility of those things changing between .NET 1.0 and .NET 1.1.
However, when running a release version, I do not get this.

Given that the versions we run are debug versions, I can't say I am
extremely concerned. I can ask around why this might happen though, and
post if I find anything.

--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message
news:%2****************@TK2MSFTNGP10.phx.gbl...

Here's a sample app. It's the same code from my first posting, with the
addition of some timing code.

Please run it in debug from the VS.Net 2003 IDE, click the button and wait.

On my environments the first exception takes anywhere from 3 to 10 seconds

to be caught. After that it's immediate.

In VS.Net 2002 the first exception is caught immediately.

Let me know what your times are.

Thanks.

"Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote

in

message news:O8**************@TK2MSFTNGP11.phx.gbl...

Robert,

If you email me a zipped project, I can take a look at it on my

machine.

--
- Nicholas Paldino [.NET/C# MVP]
- mv*@spam.guard.caspershouse.com

"Robert Gravereaux" <Ro********************@grsinc.com> wrote in message news:O7**************@TK2MSFTNGP11.phx.gbl...
> OK, I'll accept that, in general. however 5 - 10 seconds seems

excessive,

> and for the 5 - 10 seconds I'm waiting nothing appears to be happening, i.e.
> no disk activity, no libraries appear to be loading, etc...
>
> For kicks I ran the same code in debug in VS.Net 2002 on the same

machine

> and I get what I'd expect - the catch block is executed immediately the > first time. So I still think my issue is valid. I guess this is either a

> configuration issue in VS.Net 2003 or, dare I say it, a bug.
>
> Can you replicate this behaviour in your environment? I can't

believe this

> is 'normal' for VS.Net 2003, yet it happens on every install I have.
>
> "Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com>

wrote in
> message news:OI**************@TK2MSFTNGP09.phx.gbl...
> > Robert,
> >
> > Of course! The fact that it is being debugged in the first place > > changes a lot. You have one process basically hooking into

another > process
> > as it is executing code. I can't imagine that there ^wouldn't^ be

any > > overhead involved in this process, as well as initialization and
tear-down
> > code.
> >
> >
> > --
> > - Nicholas Paldino [.NET/C# MVP]
> > - mv*@spam.guard.caspershouse.com
> >
> > "Robert Gravereaux" <Ro********************@grsinc.com> wrote in

message

> > news:%2****************@TK2MSFTNGP12.phx.gbl...
> > > Thanks for the reply.
> > >
> > > It only happens when running apps in debug in the IDE. It does not occur
> > if
> > > I run the compiled executable, so I don't think I'd want to add
> additional
> > > code if possible.
> > >
> > > Is this behaviour affected by any of the settings of the debugger? > > >
> > > "Nicholas Paldino [.NET/C# MVP]" <mv*@spam.guard.caspershouse.com> wrote
> > in
> > > message news:%2****************@TK2MSFTNGP09.phx.gbl...
> > > > Robert,
> > > >
> > > > Catching exceptions is always a more expensive operation. The > > runtime
> > > > might hold of until a first occurance in order to save some time. The
> > > only
> > > > way I can think of to get around this would be to create a new
thread,
> > > > throwing and catching an exception on that thread, and then

exiting.

> > > >
> > > > Hope this helps.
> > > >
> > > >
> > > > --
> > > > - Nicholas Paldino [.NET/C# MVP]
> > > > - mv*@spam.guard.caspershouse.com
> > > >
> > > > "Robert Gravereaux" <Ro********************@grsinc.com> wrote in > message
> > > > news:%2****************@TK2MSFTNGP12.phx.gbl...
> > > > > I've noticed that the first exception thrown/caught by an app > running
> > in
> > > > > debug is very slow - it takes perhaps 7 or 8 seconds on my P4 > machine.
> > > > I've
> > > > > noticed this on several different machines running the

development

> > > > > environment.
> > > > >
> > > > > To replicate, create a new c# windows app, add a button, and

hook

it
> > to
> > > > the
> > > > > following code:
> > > > > private void btnException_Click(object sender,

System.EventArgs

e)

> > > > > {
> > > > > try
> > > > > {
> > > > > throw new ApplicationException("Exception!!!");
> > > > > }
> > > > > catch(Exception ex)
> > > > > {
> > > > > MessageBox.Show(ex.ToString());
> > > > > }
> > > > > }
> > > > >
> > > > > Run the app in debug (F5), click on the button, and wait about 5-10
> > sec.
> > > > for
> > > > > the message box to appear. Clicking a second time causes the
message
> > box
> > > > to
> > > > > appear immediately.
> > > > >
> > > > > Can anyone tell me what's causing this, and is there a
> > > > solution/workaround?
> > > > >
> > > > > Thanks.
> > > > >
> > > > > --
> > > > > Rob Gravereaux
> > > > > Principal Developer
> > > > > Glen Road Systems, Inc.
> > > > > Ro********************@grsinc.com
> > > > > http://www.grsinc.com
> > > > >
> > > > >
> > > >
> > > >
> > >
> > >
> >
> >
>
>

[Jon Skeet [C# MVP]]

Robert Gravereaux <Ro********************@grsinc.com> wrote:

Here's a sample app. It's the same code from my first posting, with the
addition of some timing code.

Please run it in debug from the VS.Net 2003 IDE, click the button and wait.
On my environments the first exception takes anywhere from 3 to 10 seconds
to be caught. After that it's immediate.

In VS.Net 2002 the first exception is caught immediately.

Let me know what your times are.

It's just over a second for me. I noted that during that second, the
CPU is busy - so it's not like the machine is just waiting or anything.

Here's a rather simpler program to demonstrate it - less GUI fluff to
get in the way:

using System;

class Test
{
static void Main(string[] args)
{
DateTime start = DateTime.Now;
try
{
throw new ApplicationException("Hello");
}
catch (Exception)
{
DateTime end = DateTime.Now;
Console.WriteLine(end-start);
}
Console.ReadLine();
}
}

Now, the interesting thing is that if you change ApplicationException
to Exception, the delay goes away.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too