How to understand data access
ANTS
Performance Profiler lets you look at all aspects of your app's data
access in one place, and understand how it relates to your .NET code.
Any queries run against SQL Server or Oracle databases are
recorded, along with how many times those queries were run and how long they
took. That information is shown alongside your .NET code, so you can quickly see
why the code you wrote resulted in those queries being executed. This can be
particularly powerful if you’re using ORMs like Entity Framework to access data,
which tend to be an impenetrable black box where performance issues can arise,
but where it’s difficult to understand why.
1. Database activity is visible in the application’s call
tree
ANTS also let you look at any HTTP requests made by your
application, so you can understand how communicating with web servers affects
performance. The URL, verb, and status code are captured, along with complete
request and response header information.
2. Detailed information about web requests
Just like with database profiling, this information is
presented in the application’s call tree, so you can understand the true cause
of any long-running, unnecessarily repeated, or failed requests.
You’re also able to look at how file system access affects
performance with File I/O profiling, which shows you a complete list of any disk
accesses your application made, along with how much data was read or written,
and how long the I/O operation took.
The ability to see all this information about data access
performance and how it relates to your code frees you from trying to manually
relate separate logs back to your code, and lets you get on with writing awesome
software instead.
What’s async code really doing?
If you’ve recently tried writing asynchronous code using
C#5’s new Async / Await keywords (perhaps for asynchronous controllers in MVC4),
you’re probably still smiling about just how much easier asynchronous
programming has become. Maybe you’re still waiting for the catch?
That moment’s likely to come when you want to
look at how your code performs. When you compile async code, behind the
scenes the .NET framework splits up async methods so that the part of a method
before an Await keyword is generally executed on a different thread to the part
after the Await keyword (the continuation). When you come to look at that code’s
performance, it isn’t possible to see how the different parts of the method are
related, which makes understand poorly-performing code nightmarishly
complicated. You also can’t see how time spent doing work asynchronously is
related to the code which caused it to run, and method names stop resembling
what you wrote as you become exposed to the async state machine’s internal
renaming system.
3. Async performance is shown in the context of the code
you wrote
ANTS Performance Profiler has a new async profiling mode, which joins
your methods back up, so you can see continuations as part of the methods they
actually belong to. ANTS can also show you how time spent on asynchronous
activity like making data access requests relates back to the method which
caused that activity to run, and presents method names as you wrote them. Now
you can now understand how your async code performs in the context of what you
wrote, and ultimately, what you need to fix to make your application run faster.
What’s next?
Learn more about
ANTS Performance Profiler, and try it on you own application with a free
14-day trial.
