Debug faster with IntelliTrace in Visual Studio 2022

[MUSIC].
>> Hi, my name is Mark Downie I'm
a Program Manager on
the Visual Studio Production
Diagnostics Team.
Today I'd like to talk to
you about IntelliTrace.
One of the weaknesses of
traditional or live debugging
is that it only understands your
applications current state.
We have very limited
data about past events.
To help you may decide to send
login flow to the output window.
You either have to infer
these past events based on the
applications current state,
or you could recreate these events
by rerunning your
application over again,
but this tends to be
really time consuming.
IntelliTrace is a Visual Studio
Enterprise feature that expands on
the traditional notion of debugging
by recording specific
events and data.
These events might include
module load activity or web
requests or breakpoints.
IntelliTrace then lets
you switch between
traditional or live debugging
and IntelliTrace debugging,
allowing you to see what
recorded information you
might have missed without
forcing a restart.
Let's see this in action.
I have this ASP.NET application.
It is an open source
application and I'm
going to use IntelliTrace
to help me keep
track of very important
events as I get deeper and
deeper into this debugging
and diagnostics session.
I'm going to go ahead and hit
"F5" and start debugging.
That will rebuild my application.
It will also start the
application for me.
It will start running
the application and load
a bunch of symbols so that
I can debug correctly.
Before I start
recreating the scenario,
I want to debug,
I'm going to go ahead and set
some strategic breakpoints
that'll help me with
my session here.
I'm going to go ahead and set
a breakpoint here at line 69.
I'm interested in the
whole action of going to
get comments for each
of the posts here.
I'm going to hit
"Control F12" which will
take me to definition
of this method.
Yeah, I'm really interested in
the data I pass to this method.
I'm interested in seeing
post ID or comments.
Let's take a deeper actually
passed those same values onto get
comments for hit "Control
F12" on line 437.
Again, this is the same
data being passed again.
I'm going to go ahead
and pass over this.
I don't need a breakpoint here.
Control F12 here takes me to
some interesting points here.
I'm interested in
seeing what the data
I get back from this method here.
That's really
interesting on line 1360
and certainly before I
returned this method back,
I'm interested into seeing if
actually even get any data here.
Let's go back to the way we
started the blog post controller
because we'll be making our way
back to the top of the call stack.
I'm certainly very interested
in if I have any blog posts and
taking a quick review there.
I'm going to go ahead and recreate
the scenario I'm debugging.
Hopefully that'll mean I hit
a breakpoint perfect
at my breakpoint.
Now this opportunity, obviously
I can review some data here,
and yeah everything seems to
be working as I would assume,
I can check values and
variables that have
been passed in at this moment.
I can check everything that's
typically what I would
expect at a breakpoint.
Fantastic. Let's keep going
as we hit 'Continue'.
We hit our next breakpoints,
which I strategically put
in another method here and
I can check the values being
passed again heating "Continue".
Again typical of what I'd expect,
I can take the date which is
back in February of 2020.
Perfect I can go here and see
exactly what information I
returned for comments I got
zero there and hit "Continue" again.
Now this is only just five.
I've only hit five breakpoints,
but you can imagine sometimes you
get several layers deep here.
You can decide at this moment
you'll notice right at the top,
what's lit up here are a
couple of additional icons.
Now these are the
IntelliTrace, step back icons,
which essentially say to you,
you have the opportunity
to go back in time.
I'm going to go ahead
and hit the "ALT,
Open Brackets", which is
the step back shortcut.
You'll see now I've changed
slightly Visual Studios,
change the top part.
Now he's describing the I'm
in historical debugging mode.
It's saying that there are
participating windows that
are also historical
debugging for me.
It's also giving me
the opportunity to
return to live debugging
at any moment.
If I look at the bottom here,
I've got autos in
historical debugging.
I've got Watch in
historical debugging,
so I can potentially add things.
They've got locals in
historical debugging,
and my Call Stack is also
historical debugging.
Instead of assuming I'm in my
controller and interaction,
it now sees that the last
time I was in this moment,
I was actually in
internal get comments,
which is the top of the call stack,
which corresponds currently
to the method I'm in.
I can take another step back.
I can hit "ALT Open Square Brackets"
again and take another step back.
I get to see now
the context of the moment
I was at this breakpoint.
Now notice I've still got this value
because obviously that
would have been executed,
forget date for entry on line 1359.
However, after this or these
values are all null because
again, there hasn't executed.
IntelliTrace has taken the snapshot
at this moment in time and
associated it correctly
with the line
I was at when the
snapshot was taken.
I can keep going back to these
moments that are important to me.
Again, going back to get comments,
I can see the values
that were passed in at
the strategic moments that were
important to my debugging session.
Now I no longer have to
remember all the details about
every single moment that led to
the era or the problem
that I'm investigating.
I can use breakpoints not
only as pausing moments,
but as moments of collecting data
that might be helpful to
me later down the line.
I can continue to go back
in time at this moment.
Or I can return to
my live debugging,
which means I'm going to basically
continue with what is
traditional live debugging.
I'm now back to the
yellow highlighted
line saying that this is the
next line to be executed.
What is also really
important is that you can
use the diagnostics tool
Windows to pick any of these
previous breakpoint moments.
If these previous
break and step moments
that allows me to hydrates
on past historical moment.
You can go to the debug
menu item Windows,
and Show Diagnostics Tool.
This opens up the diagnostics tool.
If you look at the events,
you will see a series of
these snapshots that I've taken
at each of these breakpoints.
I can choose to activate any one of
those by simply selecting
and clicking "Activate".
I can go back to a specific
historical moments
in time that I know that's
important to my current debugging.
Today I was able to demonstrate
how IntelliTrace is able to help
Visual Studio Enterprise users
expand on the traditional
notion of debugging.
IntelliTrace step back
can save you time
when you want to see the
previous application state,
but want to forgot that dozens
of restarts necessary to
get your app back into
the desired state. Thanks
for joining today.