I have deployed MoSKito stand-alone web application to monitor my own web.
I'm able to view thread, memory, time... as I expect.
However, I found that the value does not refresh at all, whenever I want to check new value, I have to press F5.
Is it the purpose of vendor, or is the configuration in somewhere?
currently there is no auto-reload function in the single view in MoSKito Inspect. MoSKito Control does support auto-reloading, but is best used if you have a cluster of web applications.
This feature was actually supported in versions prior to 2.5.x, but got removed because of low interest. If you feel, that it is an interesting and useful feature, you can always submit a ticket on projects JIRA:
https://jira.opensource.anotheria.net/browse/MSK
(or even implement it yourself and submit a pull request).
regards
Leon
Related
I have a requirement in my MVC app.
I had an export to excel functionality that is taking 3 mins of time (user clicks on a export button and waits on).
This export downloads an excel that has multiple worksheets after applying certain rules on the data.
These rules are datamanipulations plus applying colors on the cells belonging to certain columns.
Inorder to avoid the wait time, I was asked to develop a code with in the MVC app that can run like a scheduled job.
This job has to export the excel to a dedicated folder with in the network on the scheduled time (daily once).
Also i was asked to develop a web page within the app which has links to download these excels.
Quesions here (Any help would be appreciated) :
I have chosen Quartz.NET to implement this requirement. This is an open source (to my little knowledge) that can
provide the facility to schedule a job (class developed in .NET). Is it the right choice or would there be any implications in future?
Is it really needed to develop a job like code or any other way of coding can address this?
I'm not very familiar with Quartz.net, but I do know that trying to run background/scheduled tasks from within the same process as the MVC application can be problematic.
Ref 1: http://haacked.com/archive/2011/10/16/the-dangers-of-implementing-recurring-background-tasks-in-asp-net.aspx/
Ref 2: http://www.hanselman.com/blog/HowToRunBackgroundTasksInASPNET.aspx
Essentially, you can't guarantee that the process will complete correctly when running it due to how IIS handles app pools (which is where you MVC process runs: assuming hosting on IIS anyway).
You mention running a scheduled task within your MVC app. Again, this is incorrect. Why can't you just slap a console app project into the solution and drive the code from there, then put it on the server and use the Windows Task Scheduler?
In terms of background tasks, the "correct" way to do this is to send a command from your MVC app to some sort of message queue, which can then ensure that the command doesn't get dropped. I've used RabbitMQ in the past (a middleware message broker). Perhaps this is the aim of Quartz.net.
This setup typically involves another app (for me, usually a console app run on the server) that receives the command message from the message queue and runs in it's own process, entirely separate from MVC and thus the issues inherent with IIS AppPools and background tasks.
A lot of work, really... one would think it'd be easier, but that's the surefire way to do it and maintain the integrity of the task to be run.
after looking for several days for a clear answer on this I decided to just ask it here myself.
In my company I'm am tasked to make a web application that is made for Gas and Fire Detection. It talks with a modbus library over modbus tcp/ip. This connection is working verry good and it reads about 1 time each second (although I can easly adjust this).
I've red a lot about AsynControllers and async-await task in the asp.net mvc model.
The problem is I have to get this working non stop. So when my application starts for the first time(with the intention of never schutting it down since it will be a control-room kind of app), my application need to start reading and continue on reading while putting this information in a database so I can work with this database for the rest of the application. Since it fire detection this update needs to work all the time and almost instantly.
I was thinking of calling it in the global.aspx so it runs at startup. But of course when I call this method is just blocks my complete application. How can I make this work ?
Any help would be greatly appreciated.
EDIT:
it seems to work with adding:
Task.Factory.StartNew(() =>
{
ModbusDB.Main();
});
to the global.aspx!
A web application isn't meant for this sort of "always-on" model. What you're essentially talking about is two applications (which can run on the same web server):
A Windows Service (or scheduled console application, whichever you want) which does the background work of interfacing with the external system and updating the application's database. This is the "always-on" part. It polls the external system, gets the data it needs from it, updates the application database. Conversely, it can poll the application database, get the data is needs from that, update the external system. Basically, it does the ongoing background stuff.
A Web Application which handles interaction with the users. This isn't "always-on" in the strictest sense. A web application is designed to receive a request and return a response. After that interaction, it's essentially done. Just waiting for other requests. So this application would just interact with the application database and present the users with the interface they need. From the users' perspective, this application is connecting them to that external system. But from a technical perspective it's just a simple web application connecting to a simple database, something else handles the interaction with the external system.
This provides the added benefit of separating your concerns into distinct modules. If you ever need to build another application to interact with that external system (maybe some kind of system-tray-installed monitoring service on people's workstations) then all that application needs to do is interact with the database, not with the external system.
Conversely, if the external system ever changes then you only have to change that background service, not the application(s) that the users use to interact with it.
I have an ASP.NET MVC 4 app hosted as an Azure web role. I want to do something that seems like it should be pretty standard: I want to create a function that I can call that initiates a VIP swap and raises and event (or calls a callback) when the VIP Swap operation is done.
Just to add some context to the situation: My website implements a workflow that takes about an hour (or less) to complete. If I want to release a new version of the website code, it's convenient (i.e. much less "backward compatibility" code to write) to first let all of the current users complete the workflow so that the new code doesn't need to deal with data created by the previous version of the code. So a management function in my website would first poke a value into the database that disables new workflows; it would then wait until all current workflows are done; it would then call the "VIP Swap" routine; finally, when the VIP Swap routine signals its completion, it would poke the database value to re-enable new workflows.
I found the Microsoft documentation for how to programmatically initiate a VIP swap here:
http://msdn.microsoft.com/en-us/library/ee460814.aspx
The procedure involves POSTing to a magic URL and including some headers in the POST, then periodically performing a GET to a magic URL and checking the response code.
The more I think about this, the more non-trivial it seems. In addition to the basic complexities of wiring up a background timer and completion notification, I don't know what complexities, if any, I might run into trying to do this stuff in the IIS environment. Can I even perform HTTP operations on a background thread? For that matter, will I run into complications just trying to use any of the half dozen or so different "do things in the background" mechanisms baked into .NET?
Any help or guidance will be greatly appreciated. In particular, I'd be ecstatic if someone could point me at a ready-to-go implementation of this function!
I don't think you will find an easy solution to this as the fabric controller is setup to do some very fancy things without your involvement. Running hour-long workflows on a cloud computing environment, where an instance can be pulled out from underneath you, (with a maximum of 5 minutes from the OnStopping event being called to clean up) requires that you do other work anyway to make sure that all of your tasks complete.
The simple question is "What do you do if an instance goes down when workflows are still running?" Do you restart them or are they lost? If they get lost then you don't care anyway, so killing workflows for an upgrade are equally unimportant. If you re-start them then use that same mechanism to decide whether or not a node is due to be shut down, and distribute the jobs accordingly. This pattern is eerily similar to the Hadoop JobTracker. Don't just run the workflows on any 'ol instance. Submit them to a (job tracker) service that decides what to do. The (job tracker) service can then use the service management API to scale up as many instances as you need running the version that you want, run workflows on the appropriate node, and shut them down when they are no longer needed or are outdated.
Unfortunately this may not be the simple solution that you are looking for, but something in your architecture needs to change, rather than trying to force PaaS to fit with your current approach. Decompose your workloads, create loosely coupled services, design for failure, and a few other cloud/distributed computing practices need to be considered. There is a reason why Hadoop is built the way that it is — and it has a reputation for being able to get work done on a bunch of somewhat unreliable commodity hardware.
I'm writing a Rails web service that interacts with various pieces of hardware scattered throughout the country.
When a call is made to the web service, the Rails app then attempts to contact the appropriate piece of hardware, get the needed information, and reply to the web client. The time between the client's call and the reply may be up to 10 seconds, depending upon lots of factors.
I do not want to split the web service call in two (ask for information, answer immediately with a pending reply, then force another api call to get the actual results).
I basically see two options. Either run JRuby and use multithreading or else run several regular Ruby instances and hope that not many people try to use the service at a time. JRuby seems like the much better solution, but it still doesn't seem to be mainstream and have out of the box support at Heroku and EngineYard. The multiple instance solution seems like a total kludge.
1) Am I right about my two options? Is there a better one I'm missing?
2) Is there an easy deployment option for JRuby?
I do not want to split the web service call in two (ask for information, answer immediately with a pending reply, then force another api call to get the actual results).
From an engineering perspective, this seems like it would be the best alternative.
Why don't you want to do it?
There's a third option: If you host your Rails app with Passenger and enable global queueing, you can do this transparently. I have some actions that take several minutes, with no issues (caveat: some browsers may time out, but that may not be a concern for you).
If you're worried about browser timeout, or you cannot control the deployment environment, you may want to process it in the background:
User requests data
You enter request into a queue
Your web service returns a "ticket" identifier to check the progress
A background process processes the jobs in the queue
The user polls back, referencing the "ticket" id
As far as hosting in JRuby, I've deployed a couple of small internal applications using the glassfish gem, but I'm not sure how much I would trust it for customer-facing apps. Just make sure you run config.threadsafe! in production.rb. I've heard good things about Trinidad, too.
You can also run the web service call in a delayed background job so that it's not hogging up a web-server and can even be run on a separate physical box. This is also a much more scaleable approach. If you make the web call using AJAX then you can ping the server every second or two to see if your results are ready, that way your client is not held in limbo while the results are being calculated and the request does not time out.
We currently use Hp SiteScope for monitoring synthetic transactions across some of our web apps. This works pretty well except for the licensing cost for each synthetic transaction makes it prohibitive to ensure adequate coverage across our applications.
So, an alternative would be to use SiteScope's URL monitoring which can basically call a URL and then provide some basic checks for the certain strings. With that approach, I'd like to create a page that either calls a bunch of pages or try to tap into a MSTest group somehow to run tests.
In the end, I'd like a set of test cases that can be used against multiple environments to be used for production verification, uptime, status, etc.
Thanks,
Matt
Have you taken a look at System Center Operations Manager 2007?
I'm just getting started, but it appears to do what you are describing in your question.
We are looking to monitoring our data center and the a web application...from the few things I have found on the web it is going to fit our need.
Update
I've since moved to Application Insights. A great overview can be found here, https://azure.microsoft.com/en-us/documentation/articles/app-insights-monitor-web-app-availability/
There are two methods one can use, a simple ping, or record a multi-step synthetic user "experience". Basically you act as a user, and using IE and a Visual Studio Web Test project you record navigating around your site and upload that file to Azure.
For example, I record logging in, navigating a few pages, and then logging out. As long as all of those events happen in a timely manner the site is in a good operating state.
If the tests fail, take too long to respond for example, I'll get an email alerting me something isn't exactly right.