denque | The fastest javascript implementation of a double-ended queue. Used by the official Redis, MongoDB, | Runtime Evironment library

I'm working on a program which scrapes all the telegram messages, but we found out we needed a simple way of inserting and reading data(crud). I chose functional programing because oop is too imitating and too complex for me(if anyone has suggestions please hit me up because I don't know where to begin). because I wanted something like value.insert but after some research and asking cs teacher I found that this won't work.

the function finding the data:

I'm using Node + Express (running locally) and connecting to a MongoDB hosted on MongoDB Atlas. My project is a behemoth that started a while back using MDN's Local Library tutorial, and it grew as I learned how to use Express, sockets, mongo, etc. So some code in it is very bad, some is less so. Now, with a mostly feature-ready product, it's having high memory usage when multiple people connect.

Using Artillery, I have 5 users/second hit my /join_session endpoint for 20 seconds. This spikes memory usage from ~35MB to ~450MB. Full disclosure, I'm terrible at reading Chrome's Node.js Devtools for memory usage. But here's what I see under system/Context:

That array has 1024 elements. Here's the statistics tab from Chrome's inspector

So it seems like mongoose's connection pool is the problem. I haven't changed my pool size, so that's the default of 5. I set up my connection in an external file that I require in App.js.

App.js

require("./mongo.js");

mongo.js

My Mongoose requests have all been timing out since yesterday.

My internet connection is working well, the same as usual, and my source code is unchanged.

So, I think it must be a problem with my dependencies or with MongoDB itself.

Minimal reproducible example:

Some of my documents have an extra "Game" field like this

"npm list" returns this, in which there are no "unmet"s. But when I restart my server, it errors out and the error logs show "Error: Cannot find module 'async/each'" and other similar errors. I have been going through and installing each unfound module individually, but that is very tedious. What should I be doing instead?

EDIT: Also, doing "npm prune" doesn't seem to do anything ("npm list" still gives a lot of ERR-extraneous type things.)

EDIT 2: It's not a very sophisticated server, it's just meant to serve an HTML file and connect to a MongoDB. So the basic dependencies are Express, Socket.io, and MongoDB.

I have this mongoose query to get some geoNear value.

I want the fetch post from the collection 'posts' with the details of the users stored in the collection 'users'.The posts collection have ID as the (_id)userId of the users collection. I was using $lookup to retrieve the data from two collections.