External Profiler for Unity 3D apps - multithreading

Hello is there a way to profile a Process with an external profiler? I use the unity profiler but it dosent show me allocations in other threads then the main thread.

I'm pretty sure that use Unity Profiler is the best way to profile Unity authored apps/games. Unity Profiler shows allocations only on the main thread, because is there where your game code resides.
In some cases we can create our own threads to do some calculations, I imagine is this your case, so I recommend to you use ANTS Performance Profiler and ANTS Memory Profiler, I used both of them to profile ordinary .NET apps and they are really amazing profiles and, yes, they show allocations to all your app's threads.

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JavaFX : How to process a webview in a non application thread

I have a JavaFX application that contains a WebView among other JavaFx views in the same window. The WebView opens a URL to a NodeJs webapp that consumes a lot of CPU resources.
With this resource consumption from the WebView, the other JavaFX views are working slowly.
For our application, we have a very powerful system with 12 virtual threads in the processor.
So, what I need is to deport the WebView processing to another thread so that it won't affect the behavior of the other JavaFX views. Is there any way to achieve this?
You cannot do this. JavaFX has a single application thread per JVM process (java invocation) and WebView API calls must be processed on the JavaFX application thread.
Note that internally, the WebView uses WebKit which may have its own threading implementation to support html5 stuff like Web Workers, but that is all hidden from you when you are programming WebView at the Java API level. So that won't make much of a difference unless you explicitly program your JavaScript to make use of it. I guess if your NodeJS webapp is optimized for other browsers it will probably work fine in WebView, you will just need to benchmark, which I guess you did and found something wanting. You may want to expend some effort optimizing the NodeJS webapp that you have.
The only way to achieve something similar to what you are requesting in your question is to launch a separate process, i.e., a new JavaFX application in a new JVM process, that contains your WebView instance.

Monitoring Code/Method-level Statistics using AppDynamics

I am now working on Performance Testing of a Java Application that runs on GlassFish Server 4.1.
After going through some statistics that I got from AppDynamics tool, I find that there is no possibility for me to drill down to code/method level issues. For example, I can see the time taken by each method or function using dotTrace or JProfiler but AppDynamics tool seems to skip all these features.
I was also looking for a free solution, hence I choose AppDynamics. Now I feel I am not on the right track. Can someone let me know more about this tool if I am missing something or suggest any other quick and easy solution to this.
Is there a possibility that the monitors on GlassFish server 4.1 can do the same for no cost?
Generally, monitoring tools cannot record method-level data continuously, because they have to operate at a much lower level of overhead compared to profiling tools. They focus on "business transactions" that show you high-level performance measurements with associated semantic information, such as the processing of an order in your web shop.
Method level data only comes in when these business transactions are too slow. The monitoring tool will then start sampling the executing thread and show you a call tree or hot spots. However, you will not get this information for the entire VM for a continuous interval like you're used to from a profiler.
You mentioned JProfiler, so if you are already familiar with that tool, you might be interested in perfino as a monitoring solution. It shows you samples on the method level and has cross-over functionality into profiling with the native JVMTI interface. It allows you to do full sampling of the entire JVM for a selected amount of time and look at the results in the JProfiler GUI.
Disclaimer: My company develops JProfiler and perfino.

Managing multiple-processes: What are the common strategies?

While multithreading is faster in some cases, sometimes we just want to spawn multiple worker processes to do work. This has the benefits of not crashing the main app if one of the worker crashes, and that the user doesn't need to worry a lot about inter-locking stuffs.
COM+'s Application Pooling seems like a good way to achieve this on Windows. The downside is that we need to write a COM+ wrapper for the worker process.
However, when I search for Application Pooling on Google, it seems like most of its usages are related to IIS. Don't other applications (such as scientific/graphics) find it useful to spawn multiple worker processes?
So there are several questions:
Why isn't COM+ more popular in areas other than IIS? If I write a non-IIS application and want to use process management on Windows, should I go with COM+ or are there better alternatives out there?
What would be the cross platform way to do it? Are there libraries out there that give me a "process pool" (worker processes will intelligently pick up work, can be managed, etc.)
I can't offer any answers to the COM aspect of your question, but it's worth noting there's another world (besides HPC MPI) where multi-processing (rather than the more common multi-threading approach) is apparently alive, well and thriving: Python.
Why ? Python's GIL ("global interpreter lock") cripples most attempts to multithread python code so badly that multiprocessing is the generally recommended approach to parallelising Python on SMP. The standard library includes process pools; there are various other options too.
Python certainly ought to satisfy any multi-platform requirement!
You might want to investigate how the apache web server manages process pools. From version 2.0 it runs natively on windows and one of the multi-processing models it supports are process pools. A part of apache is also APR (apache portable runtime), which handles platform-specific issues.
No one can answer why something is not popular because may be no body is looking for what you are looking for. After .NET came in picture, people shifted from COM to Managed Environment, before .NET, COM and ATL and relative other technologies were quite painful to implement and they would crash and were also quite difficult to debug.
That is the reason, managed environment came in existence.
However, .NET 4 onwards, parallel libraries give much more power to user for parallel programming and also you can spawn and control other proceeses.
For multiplatform, you can look for zvrba's answer.
Yes, other applications--especially science applications--find it useful to spawn multiple processes. Since few super-computers run Microsoft Windows, scientists generally avoid using anything that ties them to a Microsoft platform. Nothing related to COM will help scientists leverage their enormous existing code base written in Fortran.
People who choose to run IIS have generally already drunk the Microsoft Koolaid, so they have fewer inhibitions to tying themselves to Microsoft's proprietary platforms, which is why COM-specific terminology will get lots of hits related to IIS.
One of the open standards for doing what you want is the Message Passing Interface. Several implementations exist and some of them run on supercomputers using Fortran. Some of them run on cheaper computers using sexier languages.
See http://en.wikipedia.org/wiki/Message_Passing_Interface
There hasn't been a mob rushing through the doors of COM application pooling primarily because of two factors:
COM is a pain in the ass to deal with compared to just about anything else
Threading can be a headache, but it's a lot easier and more convenient to manage than inter-process communication
COM application pooling was essentially created for IIS. It has one very specific benefit over normal multithreading: the multiple processes are fully isolated from each other. This is important for data security and for app stability when dealing with third party plugins of questionable stability.
Scientific computing generally doesn't need strong data security isolation between operations, and I would venture to guess that scientific computing doesn't rely much on third party plugins of questionable stability. When doing big math operations, you're either using a sexy numerics library that had better be rock solid to be taken seriously, or you're using your own code, in which case crashes should be fixed and repeat offenders should be spanked.
Oh, and all crashes except stack overflow can be trapped and dealt with within a multithreaded app, especially if it's your own code.
In short, COM app pooling is overkill for just about anything other than IIS.
Google's webbrowser chrome is a multi-process architecture software. It is open source, so you can check out its code and see how to manage processes.

Garbage Collector in Real-Time System

I'm new to C#/Java and plan to prototype it for soft real-time system.
If I wrote C#/Java app just like how I do in C++ in terms of memory management, that is, I explicitly "delete" the objects that I no longer use, then would the app still be affected by garbage collector? If so, how does it affect my app?
Sorry if this sounds like an obvious answer, but being new, I want to be thorough.
Take a look at IBM's Metronome, their garbage collector for hard real-time systems.
Your premise is wrong: you cannot explicitly “delete” objects in either Java or C#, so your application will always be affected by the GC.
You may try to trigger a collection by calling GC.Collect (C#) with an appropriate parameter (e.g. GC.MaxGeneration) but this still doesn’t guarantee that the GC won’t be working at other moments during execution.
By explicitly "delete" if you mean releasing the reference to the object then you are reliant on the garbage collector in C# managed code - see the System.GC class for ways of controlling it.
If you choose to write unmanaged C# code then you will have more control over memory, akin to C++, and will be responsible for deleting your instantiated objects, able to use pointers, etc. For more info see MSDN doc - Unsafe Code and Pointers (C# Programming Guide).
In unmanaged code you will not be at the mercy of the the Garbage Collector and its indeterminate cleanup algorithms.
I don't know if Java has an equivalent unmanaged mode, but this Microsoft info might help provide some direction on C#/.NET to use its available features for your requirement of dealing with the garbage collector.
In Csharp or Java you can't delete object. What you can do is only mark them available for deletion. The memory free up will be done by Garbage Collector.. It might be the case that Garbage Collector may not run during the life time of your application. However it's likely to run. When your system is becoming short of resources it is the most likely time when GC routines are run by the runtime. And when resources are low GC becomes the highest priority thread. So your application do get effected. However you can minimize the effect by calculating the correct load and required resources for your application life time and make sure to buy the right hardware which is good enough for that. But still you can't just bench mark your performance.
Besides just GC the managed application do get a slight overhead over the traditional C++ application due to the extra delegation layer involved. And a slight first time performance panelty since the run time needs to be up and running before your application get started.
Here are some references for developing real-time systems with the .net compact framework:
IEEE - C# and the .NET Framework: Ready for Real Time?
MSDN - Real-Time Behavior of the .NET Compact Framework
They both talk about the memory requirements of using the .net framework.
C# and Java are not for Real-Time development. Soft real-time is attainable however as you note.
For C#, the best you can do is implement the finalize/dispose pattern:
http://msdn.microsoft.com/en-us/library/b1yfkh5e(VS.71).aspx
You can request it to collect, but typically it's much better at determining how to do this.
http://msdn.microsoft.com/en-us/library/system.gc(VS.71).aspx
For Java, there are many options to optimize it:
http://java.sun.com/docs/hotspot/gc5.0/gc_tuning_5.html
Along with third party solutions like IBM Metronome as noted above.
This is a real science within CS itself.

How to monitor memory usage for managed/unmanaged code

I have an application that is built in C# .NET. It uses excel as a presentation layer and unmanged C++ as a processing engine. Is there a tool I can use to check for memory leaks for each component?
AQTime will instrument both managed and unmanaged code. I have used it successfully to find memory leaks in managed/unmanaged project.

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