wfgilman

wfgilman

Can Distributed GenStage Manage Demand Globally?

Here’s my situation: I have a pipeline for events I’d like to use GenStage to process. One stage in the pipeline makes calls to an external API with a simultaneous request limit, say 10. Creating a pipeline on one machine for this is simple, one producer and 10 consumers.

Now, for resiliency, we deploy our application to another machine and connect the nodes (AWS EC2 instances are ephemeral). The problem is now I have 20 consumers and I exceed my simultaneous request limit with the API.

Is there a way to adapter the number of consumers to a global max_demand?

I found this cool example of consumers running on multiple nodes and subscribing to a global producer. :icon_cool:

Most Liked

benwilson512

benwilson512

Author of Craft GraphQL APIs in Elixir with Absinthe

The super simple version is to just do

local_demand = total_demand / (length(Node.list))

You could totally try to have demand moved between nodes but this way the there’s no need to coordinate between nodes. If however you add more nodes part way through you have to restart stuff.

Where Next?

Popular in Questions Top

electic
Hi, I am new to Elixir. I am trying to use the DateTime component to insert a date into MySQL however the there seems to be no way to fo...
New
marius95
Hello everyone, I try to use an Javascript Event Handler in my root.html.leex file. Therefore I created a function in the app.js file: ...
New
chrisalley
ExUnit now has describe blocks which is a welcome addition coming from RSpec. In the docs, it states that nested hierarchies of describe ...
New
fireproofsocks
I’m working on defining a simple Ecto schema for a table (in PostGres), but I don’t see where I can define a column as NOT NULL. Conside...
New
vac
Hi, I’m quite new in Elixir and I’m trying to format a string to a PEM format. I have the certificate value like MIIDBTCCAe2...... and I...
New
Lily
In templates/appointment/index.html.eex: <%= for appointment <- @appointments do %> <tr> <td><%= appoi...
New
Qqwy
Original source of discussion: This topic on the Pragmatic Programmers’ Functional Web Development with Elixir, OTP, and Phoenix forum. ...
New
lucidguppy
I have a super simple question about elixir - how would I take a file like this foo bar baz and output a new file that enumerates th...
New
ashish173
I am using Ecto timestamps with postgres, I can see the timestamps() use the :naive_dateime but for my use case I wanted to store the ti...
New
dokuzbir
I want to highlight html closing tags when i click a html tag. That works in .html files but doesnt work for html.eex templates. How can...
New

Other popular topics Top

vertexbuffer
Hello, can anybody help here..? I have a list of players and I what to delete an element, but every for loop the list is reverting to ori...
New
chrismccord
As promised, the first release candidate of Phoenix 1.3.0 is out! This release focuses on code generators with improved project structure...
New
jononomo
I am trying to figure out how Mix knows whether the environment is test, dev, or prod – where is this set? Thanks.
New
belgoros
I’m not a pro in using Regex and can’t figure out why the following behaviour happens, especially if we take into account the difference ...
New
alice
Hey, Just curious what are the main benefits of Elixir compared to Clojure? When is Elixir more useful than Clojure and vice versa? Th...
New
AstonJ
Please see the new poll here: Which code editor or IDE do you use? (Poll) (2022 Edition) It’s been a while since we first asked this, I...
208 31307 143
New
boundedvariable
I am going through the kafka architecture. All the features what the kafka is providing are already in Erlang. I would like hear your opi...
New
nsuchy
Hi. I’ve noticed that Windows Powershell has it’s own IEX command and you cannot access Elixir’s IEX due to the conflict. This isn’t a cr...
New
hariharasudhan94
Lets say I have map like this fetching from my database %{"_id" => #BSON.ObjectId<58eb1a7a9ad169198c3dXXXX>, "email" => ...
New
jononomo
For some reason my phoenix channels are working for me in my local dev environment, but as soon as I deploy via Docker, I get a 403 error...
New

We're in Beta

About us Mission Statement