I like to use “Play” button in my workflow pretty frequently after small changes to scene or code.
I noticed, that the delay between clicking the “Play” button and start of the game is pretty big.
It is like 2.5 seconds on blank project (and more on complex projects).
I have i5 processor (6 cores, 4GHz turbo) and 1080ti gpu. I remember few years ago, I had much worse computer and the time on blank project was much quicker.
Is there a way I could get this delay down?
Nope, with every new version this get worse.
If you are starting a new project you can use the new experimental play mode options and disable reload domain and scene, but if you have an existing project of a decent size it’s a pain to fix everything, since the flow is much different with this new play mode, many things don’t get reset when you exit play mode.
Can you elaborate on the new play mode options? Came back to Unity after about a year so I havent heard about that.
I’ve noticed that since the release of version 2020+, the longer Unity is running, the longer it takes to enter play mode.
I’ve had Unity take as long as 20 seconds after having it running for ~4 hours, and have to periodically re-launch it when it gets to that point. Re-launching it fixes the problem temporarily.
Perhaps you’re running into the same issue?
No, but it might be a different one which I am to encounter in future 
Before I posted this thread, I created blank project and pressed Play several times and it averaged about 2.5 seconds so it havent been afflicted by the issue you are talking about.
How long is your delay? Can you get better times somehow? That would be awesome.
Go to playmode settings in the project settings and set reload scene to off and reload domain to on.
This should speed up entering playmode
Here is the docs for the new play mode. If you start a new project it is wise to code with that enabled, since it’s practically instantaneous and you can plan the code around the new behaviour.
EDIT
Some package and asset store product may not be compatible however, so I don’t know how feasible it is to use.
I don’t have any issue with the editor slowing down, mine often stays open for days.
Thank you. Will try that. Outside of that, there isnt anything else?
Btw perhaps you are expreriencing this because of some third party editor script.
Can’t be; I don’t have any third-party assets in my project. This just started happening when I updated from version 2019.x.x to 2020.x.x.
Aside from the above, I am not experiencing any delay for the play button to register my click.
It’s still very slow in Unity 2021.3.4f1. I create an empty default 2D project, I press Play, I need to wait for two seconds. There are no changes to any assets, settings or scripts. I stare at my computer screen for two seconds, my product manager is urging.
I think they not good in memory management, and memory leaks happening?
First time my 200 GB project run with start btn takes 5-6 seconds, after some hour it is horribly slow, like 15-20 seconds…
