Does anyone know anyway or library to instrument Dagger 2 and set traces to see how long each module takes to create on startup?
We are trying to reduce cold startup time of an Android time and we would like to be able to measure how much time is spent on creating each module that is built on startup so that we can track over time which modules are taking up more time, and find out where is it worth to spend time trying to defer some initializations.
I have found this online: http://frogermcs.github.io/dagger2metrics-measure-performance-of-graph-initialization/ but couldn’t really make it work
I skimmed through Dagger2 code, considering to try to add traces to the code generated tasks, but it seemed like a daunting task and we don't want to maintain a fork.
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I'm looking through my newrelic analysis and I'm seeing in almost every case over 60%-70% of my time is spent inside MixedGrailsControllerHelper.executeAction(). I've checked the traces and it's spent in executeAction() after the controller has already handled the action. So it's after invokeAction() has been called, but I can't find any locks that might be holding it up. All the time seems to be spent in executeAction(). No other methods it calls show any significant time spent in them. I am using the MongoDB gorm plugin usually returning JSON data.
So what's the problem?
I follow a book called Eclipse Plugin Development by Example: Beginner's Guide and all examples are hosted at github. However, I can't successfully run SWTBot example.
The first time it takes a very long time to run, but in the end it would pass all test cases.
However when I try to run the same code second time, it only testUI() will pass, the other three will have org.eclipse.swtbot.swt.finder.exceptions.WidgetNotFoundException: The widget was null.
Somewhere in the book is said
If one (shell) is not currently visible, it polls (every 500 milliseconds by default) until one is found or the default timeout period (5 seconds) ends when a WidgetNotFoundException is thrown
But I don't see why the first time all test cases will pass but not the second time.
but I have not idea why the first time will work but second time won't.
I also report this at github issue but so far no one response.
did you interfere with your desktop while the test was running? I found this can (!) cause problems with SWTBot.
Also, WidgetNotFound is an exception you'll be seeing a lot when using this framework. Sometimes it might be due to bugs, sometimes to unusual underlying UI code. It should be reproducible in those cases, though.
One of the new performance enhanchements for .NET 4.5 is the introduction of the 'MultiCode JIT'.
See here for more details.
I have tried this, but it seems to have no effect on my application.
The reason why I am interested is that my app (IronScheme) takes a good long time to startup if not NGEN'd, which implies a fair amount of JIT'ng is involved at startup. (1.4 sec vs 0.1 sec when NGEN'd).
I have followed the instructions on how to enable this, and I can see a 'small' (4-12KB) is created. But on subsequent startup, it seems to have absolutely no effect on improving the startup time. It is still 1.4 sec.
Has anyone actually seen (or made) this work in practice?
Also, are there any limitations on which code will be 'tracked'? Eg: assembly loading contexts, transient assemblies, etc. I ask this as the created file never seems to grow, but I am in fact generating a fair amount of code (in a transient assembly).
One bug that I did encounter was that SetProfileRoot does not seem to understand a / as a path separator, make sure to use \ .
The rule of thumb we use at Microsoft is that Multicore JIT gets you about half way towards NGEN startup performance. Thus if your app starts in 0.1 seconds with NGEN and 1.4 seconds without NGEN, we would expect Multicore JIT startup to take about 0.75 seconds.
That being said, we had to put some limitations in place to guarantee that program execution order is the same with and without MCJ. MCJ will sometimes pause the background thread waiting for modules to be loaded by the foreground thread, and will abort background compilation if there is an assembly resolve or module resolve event.
If you want to find out what's happening in your case, we have ETW (Event Tracing For Windows) instrumentation of the MCJ feature and we will be releasing a version of PerfView soon which will be able to collect these events by if you take a trace of your app startup.
Update: PerfView has been updated to be able to show background JIT information. Here are the steps to diagnosing with the latest version (1.2.2.0):
Collect a trace using PerfView of your application startup, either using Collect->Run or Collect->Collect from the main PerfView menu.
Assuming you used Collect-> Run, put the name of your .exe in the Command text box, pick a filename (i.e. IronScheme.etl), select Background JIT from Advanced Options, and click Run Command.
Close your application and double click on the IronScheme.etl file that gets generated.
Double click on the JIT Stats view in the list underneath IronScheme.etl, you should see something like this in the view that pops up:
This process uses Background JIT compilation (System.Runtime.ProfileOptimize)
Methods Background JITTed : 2,951
Percent # Methods Background JITTed : 52.9%
MSec Background JITTing : 3,901
Percent Time JITTing is Background : 50.9%
Background JIT Thread : 11308
You can click on "View Raw Background Jit Diagnostics" to see all of the MCJ events in excel. One question I forgot to ask: are you running this on a multicore machine or multicore VM? It is a common mistake to test out MCJ in a VM that only has a single logical processor.
Calling Activator.CreateInstance during startup seems to kill MCJ?
Or rather that triggered an Assembly Resolve, which completely seems to stop MCJ. And never work after that. Maybe the MSDN docs should mention this.
I need to debug a certain ViewController I have and I can't seem to pinpoint exactly what is causing my lag time for the view to show.
IS there any debugger tool in Xcode that will show me how long my methods are taking to run so i can at least find the right place to start?
Instruments has a profiler built into it ever since iOS 4.0 (before which you used a stand-alone profiler tool called Shark).
Here's a quick little tutorial that will get you started: http://blancer.com/tutorials/flex/78335/apple-profiling-tools-shark-is-out-instruments-is-in/
If you don't know about Instruments, you should. It's how you know what's really going on inside your code while it runs.
Apart from Time Profiler as suggested by Dan you can also use Sampler instrument which generally stops a program at prescribed intervals and records the stack trace information for each of the program’s threads. You can use this information to determine where execution time is being spent in your program and improve your code to reduce running time.
The main difference between sampler & Time profiler :
Sampler instrument operates upon a single process but Time Profiler operates upon a single/All processes.
To be clear, this is for a normal iPhone application, and not a game.
I've read around the web a few times some developers mentioning that they were working hard to improve/reduce the startup time of their applications, but never with any good background information on how to do so.
So the question is simple: how can you reduce the startup of iPhone applications?
Same as any other performance issue: Use Shark and/or Instruments to identify bottlenecks in your code, and then focus on how you can speed things up there. Each tool will give you a picture of how much time was spent in what parts of your code, so the general scheme would be to run the tool while you start the app and then pore over the data to see where the performance hits occur.
At app startup time, the most likely candidates for improvement will be deferring data loading until later on when it's actually needed, variously described as "on demand" or "lazy" loading. Essentially, don't load any data at app startup unless it's actually needed right away when the app loads. In practice, lots of stuff that may be needed at some point doesn't have to be immediately available when the app starts. For example, if you have a database of N records but only one is visible at a time, don't load all N into memory at app startup time. Load whatever the current record is and then load the others when you actually need them.
James Thomson did a nice blog post documenting his efforts to make PCalc launch faster.
Of particular interest is his use of image with screenshot from last app run, to pull the same trick Default.png does, while loading rest of the app.