The best cold starts are those which aren't noticed by the user. For my blog search (which runs on Lambda), I found a nice way of achieving that [1]: as soon as a user puts the focus to the input field for the search text, this will already submit a "ping" request to Lambda. Then, when they submit the actual query itself, they will hit the already running Lambda most of the times.
And, as others said, assigning more RAM to your Lambda than it actually may need itself, will also help with cold start times, as this increases the assigned CPU shares, too.
And, as others said, assigning more RAM to your Lambda than it actually may need itself, will also help with cold start times, as this increases the assigned CPU shares, too.
[1] https://www.morling.dev/blog/how-i-built-a-serverless-search...