Has anyone used windows workflow foundation for a large-scale program? We have about 200k new records faily with about a 3-week processing window. So about 5milliok active workflows at once. Has anyone done something like this? I'm hesitant to try it because it seems that Microsoft gave up on WWF.
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I am working on one project which is a standalone javafx application. It will run 24*7*365 days continuously.
So, i have a question in mind.
which things we need to consider for running this application smoothly and with high performance for 24*7*365?
Please guides me sir, regarding it.
Details for used things are as follows for Reference :-
Used java version :- 1.8.0_121
Available Ram :- 2GB
Allocated Memory for application :- -Xmx1524M
Hardware Configuration :- Processor - Intel Atom CPUD425# 1.80GHz x 2
OS :- 32 Bit Fedora 15
I will probably state the obvious here, but OutOfMemory errors are the main thing you should worry about. A small glitch in your code/program could make your app die fast or run extremely slow under memory pressure.
I would say that you need to enable garbage collection logs and monitor those. Also is there a way for a javafx app to actually use another instance if the current one is facing issues? There are tools for that under different apps, but not sure about javafx... I mean can you automatically shut down (and collect heap data) the current running application and automatically start a new one (so that later you can analyze what actually happened)? It might not be feasible, and if it's not, you should have enough stress tests before you actually lunch it into production.
One thing you should check first is whether your system suffers from the notorious memory problems that some Linux graphics drivers have. See for example my answer to this question here on SO:
Javafx growing memory usage when drawing image
I have Visual Studio 2010 and a pretty large web application project running on IIS 7. Startup for the web application is over a minute (75 seconds). I've attached ANTS to it and very little of the 75 seconds is my code. Most of it seems to be something like CreateAppDomainWithHostingEnvironment and BuildManager stuff. Now I know that ASP .NET will compile dynamically the first time but I certainly don't expect it to compile for that long. Why could I be experiencing this problem and what are some ways I can try to fix it or try to better understand what is taking so much time. Aksi the CPU utilization doesn't seem to be that high. I have an awesome machine.
The problem with the 75 second startup is that for developers working on this, everytime they make a change they have to wait this 75 seconds.
I am using .NET 4.0
EDIT
I ran Microsoft Network Monitor on my machine to see if there was anything suspicious going on the network. There wasn't as far as I can tell though i wasn't sure what to look for (I am familiar with network monitor though so I did have an idea of what I was doing). I tried to run it in release build and though it may have improved the performance a little bit its not really significant
EDIT
I have SQL Session state. As far as i can tell, the connection string is pointing local. For some reasons though, when examinning ANTS, i'm getting a lot PollLockedSessionCallback on many threads. The function seems to be called over 70 times. Does this help at all?
Try building the application in release mode. You can set this in the Build tab of the properties window. You might also consider pre-compiling when publishing the application before deployment.
Are you trying to access anything via a network share at startup? If so, bring those resources local for startup comparison.
I have a large (as in many pages, objects...) asp.net web app that pegs the server at 100% at times for no reason that i can tell. is there a way to detect what page is at fault?
I know its asp.net and not sql because task manager shows w3wp.exe as the culprit.
are there tools for doing this? or profiling .net web apps?
Check out this Red Gate product: http://www.red-gate.com/products/dotnet-development/ants-performance-profiler/
It's not trivial to master, though.
ASP.Net Tracing is the answer.
http://www.asp101.com/articles/robert/tracing/default.asp
http://www.asp.net/general/videos/how-do-i-implement-tracing-in-an-aspnet-web-site
(source: asp101.com)
If you can repeat the issue on a test server or you own machine you can use a profiler (the one included in Visual Studio 2010 or any other) to figure out what's happening.
If the problem only occurs in production you probably are best off performing a dump of the process when the problem is occuring and analyze it using DebugDiag.
Tess Ferrandez has lots of information on her blog on how to perform low level analysis of application behaviour on her blog as well, including how to use DebugDiag.
You wouldn't by chance happening to be using GC.Collect() in your web app would you? Excessive calls to GC.Collect() for large applications will cause it to spike to 100% as it scans memory to look for disposable objects. If you call GC.Collect() in rapid succession, you would likely get a continuous 100% cpu usage when memory usage is high.
I work for a hosting company, providing ASP.Net 3.5 hosting. Honestly, we usually provide quite good uptime and velocity. However, we are having problems with one of our shared pools. As usual, we try to maximize the number of webs that can run into one pool.
Lately we are suffering continuous hangs. The process doesn't crash, but starts to show OutOfMemoryExceptions or stops processing requests. We think this is responsability of one of the applications (it would be great to know which one).
I have some memory dumps that I have processed with WinDbg. I've run f.e:
!dumpheap -stat
This method provide global memory usage of objects. Nothing remarkable... Also I've checked:
~*e!clrstack
I see various non managed threads. In those who are managed appears stacks like:
[HelperMethodFrame_1OBJ: 0f30e320]
System.Threading.WaitHandle.WaitMultiple(System.Threading.WaitHandle...
0f30e3ec 7928b3ff System.Threading.WaitHandle.WaitAny(System.Threading...
0f30e40c 7a55fc89 System.Net.TimerThread.ThreadProc()...
0f30e45c 792d6e46 System.Threading.ThreadHelper.ThreadStart_Context(System...
0f30e468 792f5781 System.Threading.ExecutionContext.runTryCode(System...
At least, I haven't seen exception throwing or similar (in that moment). I've also had access to two scripts written by Tess Ferrandez for calculating the number of sessions and size. Also here not promising results. Anything peculiar or remarkable (24000 bytes as average).
I would like to know what kind of strategies are you usually using facing this kind of problems. Have you ever used Microsoft Support?
Thanks a lot!
Very nice question, well a bad asp.net can hang all shared web apps on the same pool...
Ok let see... if the problem is on memory, get the VMMap from Sysinternals, and also the Process Explorer
Run them both, and from Process explorer find the PID number of pool that you wish to investigate, its under the inetinfo.exe, and have probably the name aspnet_wp.exe.
Now on the VMMap add for monitoring this Pool using for help the PID, and voila, you see the memory and the open images (aspx files) that probably are a lot and make the problems... The files that you going to see are located on temporary of asp.net Framework, but you can connect them and see from witch site they come from.
Well if the problem is not on memory, but the programmer have create bad loops, or even create thread sleeps, then I think process explorer is a way to investigate the pools and search for whats eating the power.
Additional
Maybe a pool recycle every 15minute can solve this issue ?
More about
In those videos there are a lot of informations about VMMap and memory manager.
Mysteries of Windows Memory Management, Part 1, and , Part 2
There are many tools, but it sounds like your main goal is to determine what's causing the problem. This can be done very simply with a binary search.
Break the pool in half, and see which one crashes. Repeat until you have a crashed pool with only one application in it.
This is already O(log2n), but you can speed the process up arbitrarily by dividing into more than two sub-pools.
We have some performance problems with one of our applications. I thought about using something like dotTrace to find out where the problems are, but dotTrace would probably degrade performance even more.
What's the best way to profile an application that's on a prod environment w/o affecting performance too much?
The general answer is "don't do it".
Other than that, you can gain a lot by using performance counters. If the built-in counters don't help, you can create your own.
Among other things, the performance counters may give you an idea of how to reproduce the performance problems through load testing.
The next idea is to narrow down the area you're interested in. There's no sense impacting performance for the entire application if it turns out to be your web service access that's slow.
Next, be sure to have instrumented your application, preferably by using configuration. The Enterprise Library Logging Application Block is great for that, as it allows you to add the logging to your application, but have it configured off. Then, you can configure what kind of information to log, and where to log it to.
This gives you choices about how expensive the logging should be, from logging to the event log to logging to an XML file. And you can decided this all at runtime.
Finally, you're not going to be able to use dotTrace or something else that requires restarting IIS an adding code to your running application. Not in production. The ideas above are for the purpose of not needing to do so.
Profiling memory or cpu?
Memory: the best way would be to create a memory dump of the w3wp process (launch task manager, right click the process then "create dump"), then copy the dump to your local machine and analyse it with WinDbg. And look at which classes consume the most memory. There are lots of questions/answers here on Stackoverflow on how do do that (how to use WinDbg and analyse the .NET heap).
CPU: we use a short command-line profiler by Sam Saffron (woohoo, one of the creators of Stackoverflow!) His project is abandoned, but we forked it and maintain it here. https://github.com/jitbit/cpu-analyzer Everyone's welcome to contribute. It attaches to your threads using Microsoft's DbgManager and finds call-stacks that take longest time to execute.
Did you load-test the application on a number of sessions that's anywhere near the actual load of the production environment?
The first thing that comes to mind is that your app is not scaling well under load or that your db is not scaling well with an increase in size (causing this way problems even with a very limited number of concurrent sessions) but it could be anything really.
My suggestion is to replicate the production environment and run proper load-testing then look at the data and it'll give you some clue.
you don't wanna play games with your production environment, but if you don't have it already you could use logging to keep track of the sequence and time spans of key-events and take it from there.
You could use ants profiler
http://www.red-gate.com/products/ants_performance_profiler/index2.htm
They claim that "the overhead was hardly noticeable".
There is a 14 day free trial so you could give it a try.
Edit: I agree with John's comment, it will disrupt, require some down time, to get it started / stopped. Best to use it on a test environment to identify the bottle necks.
You can use ants profile as well as performance counter of the system. It will help you to determine whats the problem.
Here are some details about performance counter..
http://msdn.microsoft.com/en-us/library/fxk122b4.aspx
http://msdn.microsoft.com/en-us/library/ms979204.aspx
http://www.codeproject.com/KB/dotnet/perfcounter.aspx
I would recommend to take several memory dumps of the process in Production, look at all the stack traces and see if you find a pattern.