I'm trying to troubleshoot some UI issues that I've been having that I think are tied to XHR requests that I'm making on the main thread. But when I look at the network tab, I see a ton of my background worker requests and it becomes really hard to see exactly which request came from where.
Is there any way to filter the network request so that I can see if the request was initiated from a background worker (and if so, which one) or the main thread?
I added the "initiator" column to my network tab, but it just says "Other".
Thanks in advance for any help
Related
[CONTEXT]
I worked through Jake Archibald's fantastic Udacity course found here: Offline Web Applications. His work provides a Toasts dialog alerting the user that there is an update available, and they are invited to update:
Refresh / Dismiss Dialog
While this dialog is available to the user, there's a corner case on hand that I can't seem to resolve:
The service-worker can be updated any number of times prior to the client updating the local instance, pushing the numbered version of the service worker past 'just one more'. For example, the current and active service worker is #821, while the service worker that is waiting is now #824
active and waiting service workers
[PROBLEM]
I cannot find the right way to alert the browser that the next service worker to install needs to be #824, instead of #822, the dialog-box + PWA tell me that the current browser is 'redundant', and that I can't get to service-worker #824 without refreshing, and then clicking the update button.
I can recreate this with any version of Jake's code once the service-worker is set, and skipWaiting() is introduced.
I literally just want to be able to cover the corner case where the service-worker is updated 2 or more times before the user decides to update their local PWA.
You can find Jake's code on github: Jakearchibald/wittr
[ASK]: Has anyone found a solution for this corner case? If so, how do you solve it? What I'm seeing doesn't make sense as the service-worker lifecycle seems to respected per Googles documentation: service-workers/lifecyle
I did quite a bit of additional reading/research and found the following discussion threads on Github:
- Provide an easier way to listen for waiting/activated/redundant Service Workers
- Immediate Service Worker
- Recommended Approach for Refreshing Page on new SW
- Provide a one-line way to listen for a waiting Service Worker
It looks like this idea was brought up in 2017, and has for the most part gone stale. However, you can double down on using
navigator.serviceWorker.waiting.then(reg => {
if (confirm('refresh now?')) reg.waiting.postMessage('skipWaiting');
});
That will give you the ability to listen for a new Web Worker, after activating Web Worker #1, then setting Web Worker #2 to redundant, and moving Web Worker #3 into a waiting state. It's obtuse and indirect, but at least you can now move the 3# thread up and into the right slot.
A real shout-out to dfabulich, Matt Gaunt, and Beatrix Perez
We are trying to troubleshoot app pool hang scenarios, so one of the queue we thought of monitoring was http.sys queue.We need to check different parameters like app pool status and requests in queue.
Http.sys request queues are obtained from perfmon .Is there any way I can ping application pool and check status during each stage/requestload.
We are dealing this issue in two phases
1.Remove node out of HLB(we have script) once node is not responding or hung or slow, before end users complain( we get a lot of comlpaints)—priority 1
2.troubleshoot what’s the cause of hung—priority 2
Thanks in advance.
EDIT:
This article looks promising.But not able to find how to execute this.Any help on this please.
http://msdn.microsoft.com/en-us/library/ms691445(v=vs.90).aspx
I'm not sure an app pool's state will tell you if it is hung, just if it is started, stopped, or changing states.
I think you'll want to look at the IIS performance counters. I've never had to do anything like that, but the Get-Counter cmdlet is probably what you'll use.
Looks like there is another Stack Overflow question/answer that has some sample code:
Get-Counter "\\$ServerName\web service($SiteName)\current connections"):
I have a complex sync job that does several asyncronous calls for content over HTTP. Each time this content is received, it asks for the next bit and so on. These are all daisey-chained in a big over-all sync job with data on the server.
There are probably 12 steps in this job chain. It seems to get stuck after around the 5th async request, the request never comes back and it hangs for ever waiting for it. I think it may have to do with too many threads being spawned because if I fire off the one it hangs at at the beginning it returns fine.
In the way I imagine it in my head, the main thread asks for async content a. When it comes back in its own asynchronous time it spawns a new thread which then asks for aync content b. When it comes back in its own sweet time it spawns a new thread which then asks for content c. Isn't a new thread being created everytime an async request returns a result?
Am I daisy-chaining these requests right? I was quite good at threads in Java development but I'm a bit confused on how they work in Obj-C. Do I need to use a Thread pool of say 3 threads and reuse these?
Sorry for the high-level question but I'm sure some experts can help clear the cloud of mystery around this.
NSOperationQueues are built on top of Grand Central Dispatch. If you need precise control over order of operations and the ability to dispatch synchronous requests you might want to use GCD directly. Using either, you don't really need to worry about thread creation/management. You simply queue your operations as needed by your app.
The Apple docs are fine on this IMHO but you can find a number of tutorials out there.
[EDIT: added link to Apple docs]
http://developer.apple.com/library/ios/#documentation/General/Conceptual/ConcurrencyProgrammingGuide/Introduction/Introduction.html
Am new to android, am developing application with websevices using json parsing with httpget method,cant use http post method in android actually.
It working fine normally, but many time it shows the error on emulator like activity not responding force close activity.when i put that url in browser it shows the result .but i don't know why this activity not responding error came.
I think the httprequest took more time to retrieve the data from server,but am not sure. any one help me to how to avoid this error or how to minimize this .
I want know what are the possibilities to get this activity not responding error.
Thanks,
Lakshmanan
You need to perform blocking operations such as I/O in a separate thread - see the below linked resource:
http://developer.android.com/guide/practices/design/responsiveness.html:
In Android, the system guards against applications that are insufficiently responsive for a period of time by displaying a dialog to the user, called the Application Not Responding (ANR) dialog, shown at right in Figure 1. The user can choose to let the application continue, but the user won't appreciate having to act on this dialog every time he or she uses your application. It's critical to design responsiveness into your application, so that the system never has cause to display an ANR dialog to the user.
To avoid ANR (Application Not Responding) dialog,
Your business logic code is inside doBackground() of AsyncTask and You may also need to override onPostExecute(),etc. After that it is better to invoke the async task in a Service (bound or normal service).
Service:
(bound service or normal service based on your requirement)
From, android office documentation:
A service is "bound" when an application component binds to it by calling bindService(). A bound service offers a client-server interface that allows components to interact with the service, send requests, get results, and even do so across processes with interprocess communication (IPC). A bound service runs only as long as another application component is bound to it. Multiple components can bind to the service at once, but when all of them unbind, the service is destroyed.
I have a web application that I am adding workflow functionality to using Windows Workflow Foundation. I have based my solution around K. Scott Allen's Orders Workflow example on OdeToCode. At the start I didn't realise the significance of the caveat "if you use Delay activities with and configure active timers for the manual scheduling service, these events will happen on a background thread that is not associated with an HTTP request". I now need to use Delay activities and it doesn't work as is with his solution architecture. Has anyone come across this and found a good solution to this? The example is linked to from a lot of places but I haven't seen anyone else come across this issue and it seems like a bit of a show stopper to me.
Edit: The problem is that the results from the workflow are returned to the the web application via HttpContext. I am using the ManualWorkflowSchedulerService with the useActiveTimers and this works fine for most situations because workflow events are fired from the web app and HttpContext still exists when the workflow results are returned and the web app can continue processing. When a delay activity is used processing happens on a background thread and when it tries to return results to the web app, there is no valid HttpContext (because there has been no Http Request), so further processing fails. That is, the webapp is trying to process the workflow results but there has been no http request.
I think I need to do all post Delay activity processing within the workflow rather than handing off to the web app.
Cheers.
You didn't describe the problem you are having. But maybe this is of some help.
You can use the ManualWorkflowSchedulerService with the useActiveTimers and the workflow will continue on another thread. Normally this is fine because your HTTP request has already finished and it doesn't really matter.
If however you need full control the workflow runtime will let you get a handle on all loaded workflows using the GetLoadedWorkflows() function. This will return acollection of WorkflowInstance objects. usign these you can can call the GetWorkflowNextTimerExpiration() to check which is expired. If one is you can manually resume it. In this case you want to use the ManualWorkflowSchedulerService with the useActiveTimers=false so you can control the last thread as well. However in most cases using useActiveTimers=true works perfectly well.