[FIXED] Django - difference in time between big serializer and small

Issue

I'm creating a music rating app and I'm using REST Framework to create API in Django. It's super easy but I'm wondering if there is any big difference in loading time when using big serializers model and small. By big and small I mean like in getting more data. For instance I have a album page where I need to use this serializer.

"id": 2,
"title": "OK Computer",
"slug": "ok-computer",
"created_at": "2022-02-22T21:51:52.528148Z",
"artist": {
    "id": 13,
    "name": "Radiohead",
    "slug": "radiohead",
    "image": "http://127.0.0.1:8000/media/artist/images/radiohead.jpg",
    "background_image": "http://127.0.0.1:8000/media/artist/bg_images/radiohead.jpg",
    "created_at": "2022-02-22T00:00:00Z"
},
"art_cover": "http://127.0.0.1:8000/media/album/art_covers/ok-computer_cd5Vv6U.jpg",
"genres": [
    "Alternative Rock",
    "Art Rock"
],
"overall_score": null,
"number_of_ratings": 0,
"release_date": "1997-05-28",
"release_type": "LP",
"tracks": [
    {
        "position": 1,
        "title": "Airbag",
        "duration": "00:04:47"
    },
    {
        "position": 2,
        "title": "Paranoid Android",
        "duration": "00:06:27"
    }
],
"links": [
    {
        "service_name": "spotify",
        "url": "https://open.spotify.com/album/6dVIqQ8qmQ5GBnJ9shOYGE?si=L_VNH3HeSMmGBqfiqKiGWA"
    }
],
"aoty": null

This serializer is rather massive and I only need this data for Albums details page. I also pull this data in Albums list page where I list all my albums and almost all of this data is not used. If I make another serializer, little less complex and use it in albums list page, will there be a drastic difference in load speed?

And if so, can I make a Viewset where the less complex serializer is visible when I access my /albums api url and the more complex serializer is displayed when I access more specific url like /albums/1?

Solution

As you are concerned about the speed to load the objects, There is another way to improve performance. Like there are a number of methods we can use

• ModelSerializer (Slower)
• Read Only ModelSerializer (A little bit faster than ModelSerializer)
• Regular Serializer Read Only
• regular Serializer (almost 60 % faster than ModelSerializer)

Because In the writable ModelSerializer, a lot of time is spent on validations. So we can make it faster by marking all fields as read-only.

A lot of articles were written about serialization performance in Python. As expected, most articles focus on improving DB access using techniques like select_related and prefetch_related. While both are valid ways to improve the overall response time of an API request, they don't address the serialization itself.

And Yes you should go for multiple serializers instead of a BIG NESTED ONE

Answered By - Faisal Nazik