throttle | Throttle your network connection | Networking library

I develop a highly loaded application that reads data from DynamoDB on-demand table. Let's say it constantly performs around 500 reads per second.

From time to time I need to upload a large dataset into the database (100 million records). I use python, spark and audienceproject/spark-dynamodb. I set throughput=40k and use BatchWriteItem() for data writing.

In the beginning, I observe some write throttled requests and write capacity is only 4k but then upscaling takes place, and write capacity goes up.

Questions:

1. Does intensive writing affects reading in the case of on-demand tables? Does autoscaling work independently for reading/writing?
2. Is it fine to set large throughput for a short period of time? As far as I see the cost is the same in the case of on-demand tables. What are the potential issues?
3. I observe some throttled requests but eventually, all the data is successfully uploaded. How can this be explained? I suggest that the client I use has advanced rate-limiting logic and I didn't manage to find a clear answer so far.

I'm fairly new to programming (< 3 years exp), so I don't have a great understanding of the subjects in this post. Please bear with me.

My team is developing an integration with a third party system, and one of the third party's endpoints lacks a meaningful way to get a list of entities matching a condition.

We have been fetching these entities by looping over the collection of requests, and adding the results of each awaited call to a list. This works just fine, but getting the entities takes a lot longer than getting entities from other endpoints that lets us get a list of entities by providing a list of ids.

.NET 6.0 introduced Parallel.ForEachAsync(), which lets us execute multiple awaitable tasks asynchronously in parallel.

For example:

I am calling the below function which returns me Promise

I am trying to find out a way to calculate the maximum and minimum values of a column.

Using the query below, I first calculate the (requests per minute) RPM by using the summary operation and then want to pick max and min values for the RPM column.

I can technically use the take operation after ordering the column (asc or desc) to get either min or max value but it doesn't seem to be computationally efficient. Also, it only provides either max or min value and not both values at the same time.

The final output should be like following table:

I'm using sanctum for api, and all api run fine in localhost, but when run api in live server token doesn't work, any route under "auth:sanctum" middleware redirect me to "Unauthenticated", although i loged in, it loged in successfully and generate token, I passed "token" of the user in postman header, although it works fine in localhost, I tried alot of solutions but no way.

Users model:

I'm working with Laravel 5.8 and I wanted to set up a Rate Limiter that limits accessing to route by per minute and also IP address.

So I added this to RouteServiceProvider.php:

We have micro service which consumes(subscribes)messages from 50+ RabbitMQ queues.

Producing message for this queue happens in two places

1. The application process when encounter short delayed execution business logic ( like send emails OR notify another service), the application directly sends the message to exchange ( which in turn it is sent to the queue ).

2. When we encounter long/delayed execution business logic We have messages table which has entries of messages which has to be executed after some time.

Now we have cron worker which runs every 10 mins which scans the messages table and pushes the messages to RabbitMQ.

Let's say the messages table has 10,000 messages which will be queued in next cron run,

1. 9.00 AM - Cron worker runs and it queues 10,000 messages to RabbitMQ queue.
2. We do have subscribers which are listening to the queue and start consuming the messages, but due to some issue in the system or 3rd party response time delay it takes each message to complete 1 Min.
3. 9.10 AM - Now cron worker once again runs next 10 Mins and see there are yet 9000+ messages yet to get completed and time is also crossed so once again it pushes 9000+ duplicates messages to Queue.

Note: The subscribers which consumes the messages are idempotent, so there is no issue in duplicate processing

I can have 4 status ( RequiresQueuing, Queued, Completed, Failed )

1. Whenever a message is inserted i can set the status to RequiresQueuing
2. Next when cron worker picks and pushes the messages successfully to Queue i can set it to Queued
3. When subscribers completes it mark the queue status as Completed / Failed.

There is an issue with above logic, let's say RabbitMQ somehow goes down OR in some use we have purge the queue for maintenance.

Now the messages which are marked as Queued is in wrong state, because they have to be once again identified and status needs to be changed manually.

Let say I have RabbitMQ Queue named ( events )

This events queue has 5 subscribers, each subscribers gets 1 message from the queue and post this event using REST API to another micro service ( event-aggregator ). Each API Call usually takes 50ms.

Use Case:

1. Due to high load the numbers events produced becomes 3x.
2. Also the micro service ( event-aggregator ) which accepts the event also became slow in processing, the response time increased from 50ms to 1 Min.
3. Cron workers follows your design mentioned above and queues the message for each min. Now the queue is becoming too large, but i cannot also increase the number of subscribers because the dependent micro service ( event-aggregator ) is also lagging.

Now the question is, If keep sending the messages to events queue, it is just bloating the queue.

https://www.rabbitmq.com/memory.html - While reading this page, i found out that rabbitmq won't even accept the connection if it reaches high watermark fraction (default is 40%). Of course this can be changed, but this requires manual intervention.

So if the queue length increases it affects the rabbitmq memory, that is reason i thought of throttling at producer level.

1. How can i throttle my cron worker to skip that particular run or somehow inspect the queue and identify it already being heavily loaded so don't push the messages ?
2. How can i handle the use cases i said above ? Is there design which solves my problem ? Is anyone faced the same issue ?

Thanks in advance.

Check the accepted answer Comments for the throttling using queueCount

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I am trying to import the npm package superagent-throttle in my TypeScript project, but when I do so I get this message: