Django View Rendering Takes Too Long with Large QuerySet, Need Optimization Techniques
I'm working with performance optimization with a Django view that renders a large `QuerySet`. The view is supposed to return a paginated list of user profiles, but when I try to load it with more than 1000 records, it takes a important amount of time to render. I am using Django 3.2 and have the following code in my views.py: ```python from django.core.paginator import Paginator from django.shortcuts import render from .models import UserProfile def user_profiles(request): profile_list = UserProfile.objects.all() paginator = Paginator(profile_list, 20) # Show 20 profiles per page page_number = request.GET.get('page') profiles = paginator.get_page(page_number) return render(request, 'profiles.html', {'profiles': profiles}) ``` When I inspect the database queries, I notice that fetching all user profiles at once is the main bottleneck. The response time can go up to 10 seconds for the first load, which is unacceptable. I've tried using Django's `select_related` and `prefetch_related` on related fields but didn’t notice a important difference. Here’s how I attempted it: ```python profile_list = UserProfile.objects.select_related('related_field').all() ``` Additionally, I've enabled Django’s `DEBUG` mode and found that the SQL query generated is quite large. I suspect that lazy loading of relationships is contributing to the overhead. I've also considered caching the result with Django’s cache framework, but I'm unsure how to implement that effectively without running into stale data issues. Could anyone suggest strategies to optimize the view’s performance? Are there specific techniques for handling large `QuerySet` in Django effectively? Any insights would be greatly appreciated!