We are on Sitecore 8.2 with MVC and datasources for our renderings. We have found that during development the adding/selecting of a datasource for a rendering is very quick, as one would expect. But on our test servers, and even in production, this is excruciatingly slow (1-5 minutes). I started to watch our resources on the machine in question and once a user creates a new datasource item the memory and cpu spike considerably. I am looking for possible causes to this issue or areas that I can make some improvements. We have not made any customizations to the pipe lines that are used when selecting/adding/creating datasources.
Thanks,
Chris
Related
I have noticed slow performance for our web application on IIS developed under visual studio c# and vb.net.
After working for sometime on application , we notice a degradation in system performance and we have to restart IIS to restore performance again.
I have downloaded and used many tools like (debugdiag,jetbrains) to be able detect which service(s) is causing this memory leak, sometimes high cpu usage also.
Those tools give me lots of information but unfortunately ,it's all generic showing system files or string arrays etc..
Is there anyway to be able to get the applications causing this and if possible also drill down to which function or line of code causing that.
Jetbrains analysis
I have added an image showing snapshots comparison result.
Thank you
Nader
I'm developing an application using Xamarin.iOS. It is common knowledge, that its memory is handled very inefficiently and leaks are almost inevitable. That's why I'm trying to be as careful as possible and not to do anything stupid: no circular dependencies, no event listeners left unremoved, etc. I'm using Instruments to monitor resources used by my app. I have a following app design:
There is a UIViewControllerA which has a UITableView and a couple of labels/buttons. When you press on any of three table entries, you're navigated to UIViewControllerB, UIViewControllerC, UIViewControllerD respectively. It also makes a couple of HTTP requests. Each of the controllers also have labels, graphics, tables, scrollviews, buttons etc, and they also make HTTP requests. I'm testing my app by going from UIViewControllerA to those three and back, randomly. Meanwhile, I can see Real Memory column of Instrument's Resource Monitor increase by 1-2MB with every new appearance of new UIViewControllers. It never goes down. Since I don't really know, how memory should behave and since there is virtually no information on that topic, I don't know if this is considered to be a normal behavior for an iOS app. Is it okay? I do realize that my question is very vague, but I need to know if I need to pay attention to those "signs".
Without deeper knowledge of your code and what exactly it is doing, I would say it is not a normal behavior. If you switch between ControllerA, B and back to A it should also free up some memory. A good memory usage should look like a sawblade with up and downs.
The general problem is that the GC may not free up the memory immediately. If you have memory-heavy operations like image-processing you could consider to make use of GC.Collect() - but that should be your last option - to force a collection and free up some memory.
In addition to Instruments, which I also use heavily to profile my apps, is the Xamarin Profiler to gain more insights of what is still alive and keeps some references. If for some reason you can not use Xamarin Profiler use the build in tool called Heap Shot.
I'm using BreezeJS with Angular/SQL/EF/WebAPI, based on a customized version of John Papa's HotTowel template. All is working very well but I need assistance with memory management.
In my case my users download "missions" to the browser. A mission is big clump of data that I crunch locally in the browser. When the user requests a new mission, another big clump of data is downloaded. After three missions are downloaded the browser is consuming hundreds of MegaBytes of memory as shown in windows perf monitor. This browser eventually chokes. I believe the answer is to simply release/dispose the previous mission's entities. What's the best way to clean up unneeded entities so they aren't consuming memory? I've tried setDetach, nulling objects etc but memory never seems to be released.
Thanks
Mark
What are some good Profiler for asp.net mvc3 application with CPU usage details?
I have tried New Relic, Slimtune and Mini Profiler. All of them just provide what process is taking longer, but none of them actually give any insights as what is causing high cpu?
All of the above profiler did good job and we improved the process and now it no longer take long time to respond, it loads page in 300-500 ms, but now we're more concerned on CPU usage. Because sometimes application takes lots of high CPU very randomly, and we are trying to find what is causing this behaviour.
High CPU spikes can be for a number of reasons.
First thing I would do is determine if the 'random' high CPU is due to a Generation 2 garbage collections.
ASP.NET Case Study: High CPU in GC - Large objects and high allocation rates
Investigating Memory Issues
Memory Performance Counters
Garbage Collection and Performance
There are quite a few built-in performance counters that might be helpful:
ASP.NET Performance Monitoring, and When to Alert Administrators
Sam Saffron (one of the StackoverFlow authors by the way) has created a great command-line tool a while ago, but unfortunately has abandoned it.
A friend of mine forked the code to make it work in 2015:
https://github.com/jitbit/cpu-analyzer
(the page has a link to Sam's post explaining how to use it)
I am writing my own text editor, and I was wondering how can I make it load faster. Notepad.exe witch comes with windows loads almost instantly and it is a small application (on XP is 67.5KB), I know that my app is a MDI project, but it has ~900KB and it loads in 5 seconds. I could write a DLL with all bitmaps and load them from there but I don't thing that this is the solution.
Anyone has any ideea?
thanks
In one of my projects I gained a tremendous decrease in loading time by disabling the autocreation of forms. Only the mainform is created in the DPR, all others are created when needed.
Often, it's the perceived speed that's important rather than the actual speed. If you can get a splash screen up as quickly as possible and continue initializing while that's up, people will see that as faster.
Another trick is to put most of your code into DLLs and run your program on Windows startup with a special invisible mode:
myprog.exe /sneaky
which may convince Windows to leave your DLLs in memory so that, next time your application starts, it's faster.
Or even stay running in memory in invisible mode and, when the user runs myprog.exe themselves, simply make yourself visible.
Yet again, use lazy-loading DLLs for the bulk of your functionality (we've used this one under UNIX) so that it's only loaded when needed. This amortizes the loading process over the total execution time rather than taking a big hit at startup.
Those are some tricks I've heard of, there may be others.
All performance problems, can be solved by looking at the code that is executed.
Guessing what is causing the performance problems may have you spinning your wheels for a long time. When you have a performance problem, you need to profile your code. There are various tools for Delphi out there to help you do this.
Some of which are:
Automated AQTime
ProDelphi
Sampling Profiler
These and other options were discussed in this Stack Overflow Question
There are various techniques to speed up code once you have identified what the problem areas are. Since you have identified the area you want to improve, profile the start up of your application.
You may find that your creating things such as forms, resources, or other object that don't need to be created at startup.
Often applications have more than one way they can be started. Since your application is a text editor I suspect you may have a command line where you can specify the file you want to edit. Profiling the different ways you can start your application is key to make sure really know all the impacts of performance improvement.
I noticed that my project loads E_SKU327.dll and E_DAUDF1.dll about 20 times, those files belong to a shared printer (Epson Stylus), so I removed the TPageSetupDialog from my form, and it loads instantly :)
Problem solved
:)
Try to omit the code on the start and initializations sections, and see if there's any improvement, then check which section make your application load slower in this case.
and if you testing the startup time with opening text file, try to replace TMEMO (if you are using it) with SynEdit and it will load the text files a lot faster, even from Notepad ;-).