Anyone ever notice the Promise from models.player.load("context","playing"); simply doesn't come back (which is to say it neither fails nor dones)?
This doesn't happen every time I try the operation, only sporadically.
Working with API version 1.0.0, on Spotify for Windows.
Yep, timeouts don't seem to fail or done. At least I assume they're timeouts, because of their sporadic appearance, and different behavior for different users.
See later comments on my answer here: Intermittent issue with tracks snapshot for current user top list
Can be pretty frustrating. Only option I know of at this point is a success flag and a retry timer.
Related
Background
I have an AWS Lambda function (Node, currently v16) that has been doing its job for many months. It is actively maintained. One of the things it does, is download a number of images of which the URLs are supplied via the payload.
Problem
Invocations suddenly started failing sporadically. It was clear quickly that some of the requests for downloading the images were timing out. The reason for these timeouts, however, is a mystery.
Potentially useful details
A list of implementation details, debugging steps I have tried, and other random info that could shed some light on this.
For each invocation, there are typically between five and fifteen images to be downloaded.
Most invocations are successful, i.e. all images are downloaded quickly and without problems.
Invocations fail about 10-15% of the time. In most instances, only a single image fails to download. But I've also seen two or three images time out.
When retrying invocations, it is always the same image that times out. Sooner or later though, it will suddenly work. Sometimes it works on the second try, sometimes I have to wait a little longer.
Even when one invocation with a particular payload is failing, others can be successful at the same time.
When running similar code locally (same payload, same image downloading code) it never fails. So even when the images time out when the request comes from AWS Lambda, it'll still work from my machine.
Any ideas?
I am open to any suggestions, theories, or debugging ideas.
I have a ruby script that is running Capybara using selenium chrome driver.
The test navigates a website, at an unknown time a notification will appear that needs to be closed.
Is it possible to have a second thread that is polling the driver to check for the presence of the notification while the script continues perform the test.
I have tried a few different approaches, but I get errors such as Bad file descriptor (Errno::EBADF) which appears to be because the session/driver is not thread safe.
If this cannot be done, any ideas for dealing with this issue would be much appreciated. I would rather not have a piece of code I keep calling between actions, as I fear this would cause performance issues over time.
This seems like a starting point, but not 100% of what you're looking for http://blog.jthoenes.net/2013/08/16/waiting-for-a-javascript-event-with-seleniumcapybara/
Encountering a strange issue with one of our queues (for production, no less). When I try to put a message onto the queue, it's throwing an exception that simply states:
A timeout has occurred during the operation
The messages do seem to be making it onto the queue, as evidenced by the fact that I can see the queue length increasing in the management portal. However, the client application is not receiving any messages.
The management portal shows that there have been several failed requests, and also several internal server exceptions; though unfortunately I don't see any way to get more details about those failed requests and errors.
I'm somewhat at a loss as to what may have caused this, how to get more information about what's wrong, and how to move ahead in troubleshooting this. Any help would be greatly appreciated.
edit: I should mention just for completeness sake, that I did not make any changes to the clients that I'm aware of; This issue just sort of started happening all of a sudden
edit #2, woke up this morning, and things have magically returned to normal. Still not sure what happened, so I'd like to change the tone of the question to solicit suggestions as to how this kind of thing may be mitigated and/or troubleshooted (troubleshot? troubleshat? :) ) better
I have experienced this scenario too. When I tried too create a new service bus namespace, and pointed my app to this new namespace, it worked for me. This suggests that it might be some hardware failure going on (on the node where your sb-namespace resides).
Be sure to use transient failure handling, for example http://www.nuget.org/packages/EnterpriseLibrary.WindowsAzure.TransientFaultHandling/
But there might as well be required too use a "second level retry" for errors that are not transient. This you have to code yourself.
Too be more fault tolerant you can also use the new feature of paired namespaces. Here is a good resource: http://msdn.microsoft.com/en-us/library/dn292562.aspx
Hth
//Peter
I've recently started programming in C on my Raspberry Pi. I have downloaded libspotify (I have the correct version), and have managed it pretty well.
Just recently (~2 hours ago (around 18:00 30/12/2013)), libspotify started to return SP_ERROR_OTHER_PERMANENT when checking for a search error in the search_complete_cb callback.
Before the error started occuring, I have built and started the program quite a few times (and thus, logging in many times, during only a short period of time), and to test my 'Search' feature, I have used the same query every time. Then, without making any changes to my program, suddenly there were no results returned after calling sp_search_create.
I am worried that the developer account has been somehow suspended for either repeatedly logging in, or because it seemed weird to the spotify crew that I would search for the same query all the time. I don't really know what the problem is caused by. There are no emails or warnings sent to the address connected to the account. The problem has lasted for a while now, so it seems like it's not going away at first.
Additional details
log_message tells me there is a ChannelError(4, 0, search). I have also seen ChannelError(5, 0, search), but only once.
I can still play music from the official Spotify desktop client for Windows.
I have an earlier version of the program, before I rewrote it to get a bit more structure, that works. The same API key and same credentials are used in both programs, so that excludes a ban. The rewrite does log in, but no results are returned from searching. In the old version, I get a lot of results. All working. I have rebooted the Raspberry Pi several times, but that doesn't seem to help.
If you need any code or other information, I'll be happy to share. Just point out what's needed, because the code is split over a lot of files.
Well, if your old one is working then the problem will be in your rewrite. Don't pay too much notice to the error messages, they're pretty much par for the course, and can be triggered by something as benign as a cache miss. Unless you're actually getting an error callback somewhere, the log messages are meaningless.
As for your problem, I can't really make any guesses without seeing your code. One thing to check and is the most common course of a permanent error is to make sure you're actually logged in. The login process is asynchronous, and any functionality that requires you to be logged in (searching is one of them) will fail before login is completed.
I'm having trouble with my Meteor app when it gets to its peak amount of traffic (peak for this is nothing, 1k visits, maybe 2,500 pageviews in a day). CPU usage spikes and never recovers, so I've taken to using Nodetime to monitor usage and I've been reloading the process (forever restart) to get things back to normal.
I'm fairly new to profiling, so finding the underlying cause has me at a loss for where to start. I'm fairly certain it has to do with my app's server code, but the profiling seems to point to the Fibers module as a "hotspot" which I understand aids in making my server code synchronous.
Below is a snippet from the profiling results. I hope someone can guide me in the right direction in troubleshooting this!
While I don't have a specific answer to your question, I have experience dealing with CPU issues for our production meteor app for so I can give you a list of things to investigate.
Upgrade to the latest version of meteor and the appropriate node version (see the changelog). As of this writing that's meteor 0.8.2 and node 0.10.28.
Read this and this article. The latter makes a great point that you really should always try to delay activation of subscriptions until you need them. In particular you may not need to publish anything for users who are not logged in. In my experience, meteor CPU problems have everything to do with subscriptions.
Be careful with observe and observeChanges. These are expensive and are easy to abuse. In particular:
Make sure you are calling stop() on your handles when they are no longer needed (consider using a package like publish-with-relations so this is done for you).
Fetch only the collections and fields that you absolutely need. Observe works by continually diffing objects (requires lots of CPU). The fewer and smaller objects you have, the less there is to compute.
Consider using smart-collections before it is retired. Use oplog tailing - this can make for a night and day difference in performance and CPU usage in your app.
Consider making some things not reactive (also mentioned in the articles above). For us that was a big win. We had one extremely expensive join that was used on two frequently accessed pages on the site. When it got to the point where the CPU was pegged at 100% about every 30 minutes I gave up on reactivity for that element and just did the join on the server and shipped the data to the client via a method call. I also created a server-side expiring cache for these results and stored them by user (special thanks to Matt DeBergalis for this suggestion).
Do a preventative nightly restart. I have a cron job that tells forever to restart our app once a day in the middle of the night. That brings the CPU down from ~10% to 1%. This seems like black magic, but the fact that the CPU usage changes after a reset leads me to believe this is a good idea.
Updated thoughts (1/13/14)
We migrated to oplog tailing as soon as it was available (meteor 0.7) and that made a big difference. Note that in order to get access to the oplog, you'll probably need to either host your own db or run a dedicated instance on the hosting provider of your choice. I'd also recommend adding the facts package to actually tell if its working.
There was a memory leak discovered in publish-with-relations, and as of this writing the atmosphere version (v0.1.5) hasn't been bumped to reflect these changes. If you are using it in production, I strongly recommend checking out the HEAD version and running it locally.
We stopped doing nightly restarts a couple of weeks ago. So far everything has been fine (fingers crossed).
Updated thoughts (7/2/14)
A few months ago we switched over to using an Elastic Deployment on mongohq. It's affordable, the performance has been great, and they even have a blog post which tells you how to enable oplog tailing.
I'd strongly recommend checking out kadira to help diagnose performance issues in your app. Also check out the academy articles which have a number of good tips in them.
I'm also having this problem. Actually there is an issue with 0.6.6.1, I run meteor --release 0.6.6 and the cpu is back to normal now.