We would like to know if there's any way we could configure our site so when we load a page, the DXA loads all the components of that page in parallel, instead of sequentially. We are working with DXA 1.8 .Net and Tridion 8.5.
Thanks a lot
DXA 1.8 is still a MVC application and the default model builder (here) loads all the regions and entities included in the page model, provided you are using embedded component presentations.
You can set the view model caching value to true in your web.config, if there are performance concerns.
Elaborate your question, if there is a specific reason that you are looking at to load the CPs any differently.
As Shiva explained in his answer, OOTB this is not possible. But you can extend DXA solution to serve your solution. DXA provides a good set of extension points including creation of custom model builder. I believe you can write your own model builder(similar to DefaultModelBuilder) and there you can use asynchronous method to load Entity model.
Above solution should work for you but avoid it until you have valid reason to use it. It can create some issue while upgrading the project. Fyi, DXA 2.0 introduces independent model service which adds another layer of caching to improve the load speed of your website pages.