I've recently begun using the Web Deployment Accelerator for my Windows Azure account. It is providing an immediate return in time saved and is an excellent offering.
However since "everything" is now stored to Azure Storage rather to the regular E:Drive I am immediately seeing a cost consequence for using the tool.
In one day I have racked up a mighty 4 cent NZD charge. In order to do that I had to burn through about 80,000 storage transactions and frankly i cant figure where they all went.
I uploaded 6 sites that are very small wouldn't have more than 300 files each. So I'm wondering:
a. is there is a profiling tool for the Web Deployment Accelerator that will allow me to see where and how 80,000 storage transactions were used for such a small offering. Is it storage transaction intensive tool? Has any cost analysis been carried out in terms of how this tool operates? Has it been optimised with cost in mind?
b. If I'm using this tool do i pay for 2 storage transactions per http request to a site? As since the tool now writes the web server logs to table storage, that would be one storage request to pull the http request resource (img, script, etc) and a storage request to write the log entry as well would it not?
I'm not concerned about current charges I 'm concerned about the future if i start rolling all my hosted business into the cloud. I mean Im now being charged even just to "look" at my data right? If i list the contents of a storage folder using a tool like Azure Storage Explorer that's x number of storage transactions where x = number of files in the folder?
Not sure of a 3rd-party profiler tool, but Windows Azure Storage logging and metrics will give you very detailed info regarding both individual accesses and hourly rollups. It's pretty straightforward to enable, and the November 2011 SDK includes support for the API calls required for enabling. See here for an overview of what's offered for metrics and logging.
My team worked with Fullscale180 to build a storage library, Azure Store XRay, to demonstrate how to enable and query storage metrics and logging. Note: This was published before the SDK had logging and metrics support, so it uses the REST API calls instead. But that won't impact you if you try to use the library.
You can also look at another code demo, Cloud Ninja, which calls the XRay library for its metrics display (see here for running demo).
Regarding querying storage for objects in blob containers: that's not a 1:1 transaction:file scenario. You can specify the maximum number of blobs to return when listing items in a container. It's possible that all blobs are returned in one transaction. Of course, if you then grab each blob, each of these will be at least one transaction (depending on blob size). See here for details about listing blobs.
Related
I want to use Azure to handle long running tasks that can’t be handled solely by a web server as they exceed the 2 min HTTP limit (and would put unnecessary load on it regardless). In this case, it’s the generation of a PDF report that can take some time (between 2-5 mins). I’ve seen examples of solutions for this using other technologies (Celery, RabbitMQ, AWS Lamda, etc.) but not much using what's available on Azure (Functions and Storage in this case).
Details of my proposed solution are as follows (a diagram is here)
API (that has 3 endpoints):
Generate report – post a message to Azure Queue Storage
Get report generation status – query Azure Table Storage for status
Get report – retrieve PDF from Azure Blob Storage
Azure Queue Storage
Receives a message from the API containing parameters of the requested report
Azure Function
Triggered when a message is added to Azure Queue Storage
Creates report generation status record in Azure Table storage, set to ‘Generating’
Generate a report based on parameters contained in the message
Stores output PDF in Azure Blob Storage
Updates report generation status record in Azure Table storage to ‘Completed’
Azure Table Storage
Contains a table of report generation requests and associated status
Azure Blob Storage
Stores PDF reports
Other points
The app isn’t built yet – so there is no base case I’m comparing against (e.g. Celery/RabbitMQ)
The time it takes to run the report isn’t super important (i.e. I’m not concerned about Azure Function cold starts)
There’s no requirement for immediate notification of completion using something like Webhooks – the client will poll the API every so often using the get report generation endpoint.
There won't be much usage of the app, so having an always active server to handle tasks (vs Azure Function) seems to be a waste of money.
If I find that report generation takes longer than 10 mins, I can split it up into more than one Azure Function (to avoid consumption plan hard limit of 10 mins execution time per function)
My question is essential whether or not this is a good approach (to me it seems good, and relatively cost-effective, I’m just not sure if there’s something I’m missing).
This can be simplified using Durable Functions. Most of the job is already handled by the framework and you also can query an endpoint to check for the completion status.
https://learn.microsoft.com/en-us/azure/azure-functions/durable/durable-functions-overview?tabs=csharp
I want to build a image sharing platform for customers to use. This platform will take an image provided by a user, create copies of it at multiple resolutions, and store them ready to be shared or downloaded. How to achieve this using azure in a cost effective ways
Im thinking to use Azure functions(for the api calls) storage blobs , event grid and cosmos db for the same.
To keep the costs low keep it simple:
Store data in Blob storage. Price varies based on redundancy, speed of access and location
Azure functions for processing images, consumption plan gives 1M free requests per month
Azure app service to host web site for uploading images, there is a free tier
Short Version
We want to migrate to v4 and our app names are less than 32 symbols.
Should we migrate to dedicated Storage Accounts or not?
Long Version
We use Azure Functions v3. From start one Storage Account was shared between 10+ Azure Function Apps. It could be by luck but the names are less than 32 symbols and it is not going to change. We are not using slots as they were initially not recommended and then with no adoption time or recommendation made generally available.
Pre-question research revealed this question but it looks like more related to the durable functions. Another question looks more up the point but outdated and the accepted answer states that one Storage Account can be used.
Firstly, the official documentation has a page with storage considerations and it states (props to ijabit for pointing to it.):
It's possible for multiple function apps to share the same storage account without any issues. For example, in Visual Studio you can develop multiple apps using the Azure Storage Emulator. In this case, the emulator acts like a single storage account. The same storage account used by your function app can also be used to store your application data. However, this approach isn't always a good idea in a production environment.
Unfortunately it does not elaborate further on the rationale behind the last sentence.
The page with best practices for Azure Function mentions:
To improve performance in production, use a separate storage account for each function app. This is especially true with Durable Functions and Event Hub triggered functions.
To my greater confusion there was a subsection on this page that said "Avoid sharing storage accounts". But it was later removed.
This issue is somehow superficially related to the question as it mentions the recommendation in the thread.
Secondly, we had contacted Azure Support for different not-related to this question issues and the two different support engineers shared different opinions on the current issue. One said that we can share a Storage Account among Functions Apps and another one said that we should not. So the recommendation from the support was mixed.
Thirdly, we want to migrate to v4 and in the migration notes it is stated:
Function apps that share storage accounts will fail to start if their computed hostnames are the same. Use a separate storage account for each function app. (#2049)
Digging deeper into the topic, the only issue is the collision of the function host names that are used to obtain the lock that was known even in Oct 2017. One can follow the thread and see how in Jan 2020 the recommendation was made to update the official Azure naming recommendation but it was made only on late Nov 2021. I also see that a non-intrusive, i.e. without renaming, solution is to manually set the host id. The two arguments raised by balag0 are: single point of failure and better isolation. They sound good from the perspective of cleaner architecture but pragmatically I personally find Storage Accounts reliable, especially if read about redundancy or consider that MS is dog-fooding it for other services. So it looks more like a backbone of Azure for me.
Finally, as we want to migrate to v4, should we migrate to dedicated Storage Accounts or not?
For the large project with 30+ Azure Functions I work on, we have gone with dedicated Storage Accounts. The reason why is Azure Storage account service limits. As the docs mention, this really comes into play with Durable Task Functions, but can also come into play in other high volume scenarios. There's a hard limit of 20k requests per second for a Storage Account. Hit that limit, and requests will fail and will return HTTP 429 responses. This means that your Azure Function invocation will fail too. We're running some high-volume scenarios and ran into this.
It can also cause problems with Durable Task Functions if two functions have the same TaskHub ID in host.json. This causes a collision when Durable Task Framework does its internal bookkeeping using Storage Queues and Table Storage, and there's lots of pain and agony as things fail in spectacular fashion.
Note that the 20k requests per second service limit can be raised with a support ticket to Azure. If approved, the max they'll raise it to is 50k requests/second.
So avoid the potential headaches and go with a Storage Account per Function.
We are using an Azure Storage account to store some files that shall be downloaded by our app on the users demand.
Even though there should be no write operations (at least none I could think of), we are exceeding the included write operations just some days into the billing period (see image).
Regarding the price it's still within limits, but I'd still like to know whether this is normal and how I can analyze the matter. Besides the storage we are using
Functions and
App Service (mobile app)
but none of them should cause that many write operations. I've checked the logs of our functions and none of those that access the queues or the blobs have been active lately. There are are some functions that run every now and then, but only once every few minutes and those do not access the storage at all.
I don't know if this is related, but there is a kind of periodic ingress on our blob storage (see the image below). The period is roundabout 1 h, but there is a baseline of 100 kB per 5 min.
Analyzing the metrics of the storage account further, I found that there is a constant stream of 1.90k transactions per hour for blobs and 1.3k transactions per hour for queues, which seems quite exceptional to me. (Please not that the resolution of this graph is 1 h, while the former has a resolution of 5 minutes)
Is there anything else I can do to analyze where the write operations come from? It kind of bothers me, since it does not seem as if it's supposed to be like that.
I 've had the exact same problem; after enabling Storage Analytics and inspecting the $logs container I found many log entries that indicate that upon every request towards my Azure Functions, these write operations occur against the following container object:
https://[function-name].blob.core.windows.net:443/azure-webjobs-hosts/locks/linkfunctions/host?comp=lease
In my Azure Functions code I do not explicitly write in any of container or file as such but I have the following two Application Settings configured:
AzureWebJobsDashboard
AzureWebJobsStorage
So I filled a support ticker in Azure with the following questions:
Are the write operation triggered by these application settings? I
believe so but could you please confirm.
Will the write operation stop if I delete these application settings?
Could you please describe, in high level, in what context these operations occur (e.g. logging? resource locking, other?)
and I got the following answers from Azure support team, respectively:
Yes, you are right. According to the logs information, we can see “https://[function-name].blob.core.windows.net:443/azure-webjobs-hosts/locks/linkfunctions/host?comp=lease”.
This azure-webjobs-hosts folder is associated with function app and it’s created by default as well as creating function app. When function app is running, it will record these logs in the storage account which is configured with AzureWebJobsStorage.
You can’t stop the write operations because these operations record necessary logs to storage account used by Azure Functions runtime. Please do not remove application setting AzureWebJobsStorage. The Azure Functions runtime uses this storage account connection string for all functions except for HTTP triggered functions. Removing this Application Settings will cause your function app unable to start. By the way, you can remove AzureWebJobsDashboard and it will stop Monitor rather than the operation above.
These operations is to record runtime logs of function app. These operations will occur when our backend allocates instance for running the function app.
Best place to find information about storage usage is to make use of Storage Analytics especially Storage Analytics Logging.
There's a special blob container called $logs in the same storage account which will have detailed information about every operation performed against that storage account. You can view the blobs in that blob container and find the information.
If you don't see this blob container in your storage account, then you will need to enable storage analytics on your storage account. However considering you can see the metrics data, my guess is that it is already enabled.
Regarding the source of these write operations, have you enabled diagnostics for your Functions and App Service? These write diagnostics logs to blob storage. Also, storage analytics is also writing to the same account and that will also cause these write operations.
For my case, I have a Azure App Insight which took 10K transactions on its storage per mintues for functions and app services, even thought there are only few https requests among them. I'm not sure what triggers them, but once I removed app insights, everything becomes normal.
I want to pull large amount of data, frequently from different third party API web services and store it in a staging area (this is what I want to decide right now) from where it will be then moved one by one as required into my application's database.
I wanted to know that can I use Azure platform to achieve the above? How good is it to use Azure platform for this task?
What if the data to be pulled is of large amount and the frequency of the pull is high i.e. may be half-hourly or hourly for 2,000 different users?
I assume that if at all this is possible, then the bandwidth, data storage and server capability etc. will not be a thing to worry for me but for ©Microsoft. And obviously, I should be able to access the data back whenever I need it.
If I would have to implement it on Windows Servers, then I know that I would use a windows service to do this. But I don't know how it can be done for Windows Azure Platform if at all it is possible?
As Rinat stated, you can use Lokad's solution. If you choose to do it yourself, you can run a timed task in your worker role - maybe spawn a thread that sleeps, waking every 30 minutes to perform its task. It can then reach out to the Web Services in question (or maybe one thread per Web Service?) and fetch data. You can store it temporarily in Azure Table Storage, which is a fraction of the cost of SQL Azure (0.15 per GB), and then easily read it out of Table Storage on-demand and transfer to SQL Azure.
Assuming you host your services, storage and SQL Azure are in the same data center (by setting the affinity appropriately), you'd only pay for bandwidth when pulling data from the web service. There'd be no bandwidth charges to retrieve from Table Storage or insert into SQL Azure.
In Windows Azure that's usually Worker Role used to host the cloud processing. In order to accomplish your tasks you'll either need to implement this messaging/scheduling infrastructure yourself or use something like Lokad.Cloud or Lokad.CQRS open source projects for Azure.
We use Lokad.Cloud for distributed BI processing of hundreds of thousands of series and Lokad.CQRS allows to reliably retrieve and synchronize millions of products on schedule.
There are samples, docs and community in both projects to get you started.