Kibana UI takes over 10 seconds on initial load

[Gavin_Clark]

Hey team, long time reader, first time poster. We have a weird issue ever since upgrading to Kibana and elasticsearch 7.7.1. What we'll see is sometimes the UI(doesn't matter on module, could be Discover, Dashboard, Management etc) will sit on the Kibana loading screen for as long as 15 seconds before loading the page. Any subsequent requests are fast once the page is loaded so it doesn't appear to be a data issue but a UI issue. We see multiple .js bundles taking a few seconds each during this time.

On times where the page loads quickly it does not download the bundles in the attached screenshot. Are these items sometimes cached and sometimes not? What can I check to see why the UI is slow to load initially?

We did not have this issue on 6.8.9 and have changed nothing on our kibana instance(t3.large).

[cheiligers]

@Gavin_Clark Congratulations on your first post!

The short answer is that Kibana on 7.7.1 effectively contains many smaller apps and each has to load its own bundle.
The good news is that the entire codebase (over a million lines of code) has been migrated (refactored) and performance has improved. You can read more about it here

[Gavin_Clark]

I'm excited to here that they refactored and improved performance, doing that for an entire codebase is no small task.

The issue I'm seeing is that this has actually made things significantly slower, specifically the initial UI load. Are there things we can disable(since you say there are many smaller apps each loading their own bundle) to try and get some performance back? If it remains this slow we'll have to revert back to a less secure version due to complaints from our engineers on the speed.

[cheiligers]

Hey Gavin,
When you say 'things we can disable', the answer depends on how you're running Kibana. If you're running from the source code (cloned repo), then you could look into the optimization and bundling processes within the root of the project. I'm afraid I'm not too familiar with the intricacies on the older versions.
If you can, rather than reverting back to a previous version, try upgrading instead to 7.8! That's the first build where we saw significant load time improvements.