Questions & Help>Questions

Time Sensitive Functionality in Elixir

/phoenix#timestamps
chrisstpierre

chrisstpierre

Time Sensitive Functionality in Elixir

I need to understand more clearly how the runtime & scheduler works in regards to time sensitive functionality.

  1. I would like to measure the response time of an HTTP Request to an external server. I want this measurement to be the exact time it took for the external server to respond. I can record the time it takes for the function to finish, but if the CPU is busy, etc this might not be the true response time. What is the best way to do this and why?

  2. I want to run repeat cron-like tasks on a timer. How confident can I be that the task will run at the exact given time? If I overload it - say by scheduling 10,000 tasks at the same time - what will happen? Will they be scheduled in order? And can I retrieve the actual execution time?

In general I am still trying to understand when Asynchronous code should be a Process / Stream / GenServer / Task / Agent, and any guidance / resources here would be great!

This is a Phoenix project.

Thanks!

5 comments
#timestamps
2 1565 5

First Post!

hubertlepicki

hubertlepicki

Looks like you don’t want to overload your server then. You can limit the concurrency with something like GenStage, custom dynamic task supervisor or Poolboy. If you do overload your server, you not only get the wrong measurements, but your whole system will be, well, overloaded, slow and less responsive.

Having said that, Elixir/Phoenix does scale well when it comes to handling many concurrent I/O tasks like making HTTP requests. So it might simply not get overloaded. But if it does, limiting concurrency would be my first task to look at.

Post #2

Where Next?

View thread on forum (has 5 responses!)
phoenix
timestamps
Home Questions & Help>Questions
/phoenix#timestamps
2 1567 5
Last post

Popular in Questions Top

dotdotdotPaul
Questions & Help>Questions

Ecto: Validating belongs_to association is not nil?
Okay, I'm having a heck of a time trying to figure out how to best handle the validation of belongs_to associations in Ecto. I'm sure I'...
#ecto
29 17806 25
New
fireproofsocks
Questions & Help>Questions

Defining Ecto Schemas (PostGres) to use NOT NULL in column definitions
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...
#ecto
29 14078 4
New
lk-geimfari
Questions & Help>Questions

The most correct way to read a JSON file
What is most correct way to open, read and parse JSON file with poison? For example if we have example.json file in root of some projec...
23 13679 2
New
vac
Questions & Help>Questions

Formatting a string to PEM with headers and line breaks
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 ...
2 14555 7
New
makeitrein
Questions & Help>Questions

Extracting numbers from a string
Hey all, just started picking up Elixir last week and am writing a scraper as a learning project. Baby step #1 is extracting the number ...
#code-review#regex#troubleshooting
38 14381 20
New
qwerescape
Questions & Help>Questions

How to get the call stack/stack trace at any point in code?
Is there a way to get the call stack or stack trace at any point in the code? Not from exceptions, but an expression that returns how the...
53 15772 4
New
mathew4509
Questions & Help>Questions

Iterating through a list
I have a list say x = ["23gh", "56kh", "97mh"] I would like to pass each element to Val in each iteration. Say, in iteration 1 -------...
#book-programming-elixir#enumerables#enum#list
3 12090 5
New
shahryarjb
Questions & Help>Questions

How to convert map to string (separated with ,)
Hello, I have map which I want to convert it to string like this: the map: %{last_name: "tavakkoli", name: "shahryar"} the string I ne...
#maps#strings
15 15491 2
New
beno
Questions & Help>Questions

Pattern match with multiple match options
I will often find my self writing things similar to: case some_value do nil -> something() "" -> something() _ -> someth...
#pattern-matching#how-to-question
29 15490 6
New
siddhant3030
Questions & Help>Questions

How can I write a raw sql query?
Hi, I have to write a raw query for one of my project. But till now I have used ecto queries and don’t have much experience writing raw ...
/phoenix#ecto
13 19061 20
New

Other popular topics Top

Qqwy
Blogs & Podcasts>Blog Posts

Elixir Blog Posts
Update: How to use the Blogs & Podcasts section You can post links to your blog posts or podcasts either in one of the Official Blog...
hexdocs.pm
#blog-posts#wiki#stickies#official-blog-posts-thread
3268 119930 1237
New
dotdotdotPaul
Questions & Help>Questions

Ecto: Validating belongs_to association is not nil?
Okay, I'm having a heck of a time trying to figure out how to best handle the validation of belongs_to associations in Ecto. I'm sure I'...
#ecto
29 17806 25
New
itssasanka
Questions & Help>Questions

Why use `utc_datetime` over `naive_datetime` for Ecto?
Hi all, Trying to get some more clarity over utc_datetime and naive_datetime for Ecto: https://hexdocs.pm/ecto/Ecto.Schema.html#module-...
#ecto#timestamps#datetime#timezones
115 14814 19
New
sergio_101
Questions & Help>Questions

Pattern matching against a string
I am VERY much an elixir newbie. I have taken one elixir course and one phoenix course on Udemy. During that course, I saw the instructor...
#pattern-matching
27 26685 14
New
jononomo
Questions & Help>Questions

Where / How does the Mix environment variable get set?
I am trying to figure out how Mix knows whether the environment is test, dev, or prod -- where is this set? Thanks.
#mix
31 22791 9
New
script
Questions & Help>Questions

Removing spaces and characters from string
If I have a string “1000 cfu/ml” . I want to remove the characters and / and space . So the string is like this "1000" What is the ...
#regex
11 14427 2
New
vac
Questions & Help>Questions

Formatting a string to PEM with headers and line breaks
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 ...
2 14555 7
New
myronmarston
Questions & Help>Questions

Typespecs - best way to spec keyword lists?
The Elixir Typespec docs show the following syntax for keyword lists in typespecs: # ... | [key: type] # keyword lis...
#dialyzer
52 14258 3
New
stefanluptak
Questions & Help>Questions

Using VSCode on multiple monitors
Hello everybody, usually, I use a 29" ultra-wide monitor for VSCode which can easily accomodate explorer (files panel) + file with code ...
#vscode#vscode-elixir
7 17615 6
New
baxterw3b
Questions & Help>Questions

Anonymous functions with multiple body
Hi guys, i’m new in the Elixir world, and i have to say, that i love it! i’m having some problem to understand anonymous functions with ...
19 21396 4
New
Back to top

Latest Phoenix Threads

Phoenix Forum ❯

Questions & Help>Questions

Questions Questions ❯

Latest on Elixir Forum

Elixir Forum ❯

Sponsor Spotlight

ElixirCasts

Producing high quality Elixir screencasts since 2017.

Our Sponsors

Dashbit

Build Elixir applications with speed and confidence.

EEF

Supporting innovation across the BEAM ecosystem.

Coders51

We build reliable cloud platforms for business-critical systems.

AppSignal

Catch errors, track performance, monitor hosts and more.

ElixirCasts

Producing high quality Elixir screencasts since 2017.

WyewWorks

Enabling companies to succeed by building software people love.

Potions

The deployment platform built for Elixir: PaaS ease, VPS control.

Pragmatic Studio

Courses that'll move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

Categories:

Sub Categories:

Forums

Our Sponsors

Dashbit

Build Elixir applications with speed and confidence.

EEF

Supporting innovation across the BEAM ecosystem.

Coders51

We build reliable cloud platforms for business-critical systems.

AppSignal

Catch errors, track performance, monitor hosts and more.

ElixirCasts

Producing high quality Elixir screencasts since 2017.

WyewWorks

Enabling companies to succeed by building software people love.

Potions

The deployment platform built for Elixir: PaaS ease, VPS control.

Pragmatic Studio

Courses that'll move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

We're in Beta

About us Mission Statement