My guess is that a lot of memory in the browser is shared.
Another commentor in this thread wrote that VS Code is incredible efficient for a Electron app.
Re:Electron 2.0.0 beta
by danielbarla on Thursday February 22, 2018 @08:16AM
(#16437313)
That could certainly account for some of the memory usage. I'm still confused about why there would be a 10% cpu usage on one, and not on the browser version (especially if they are equivalent, or even share underlying code).
VS Code certainly is efficient for an Electron app, and I'm sure it's really hard to achieve that level of efficiency. To be honest though, I use it side by side with Visual Studio itself, and on many metrics, it eats its big brother for breakfast (e.g. [1])... and that is a native app. One can argue that it's apples and oranges, and that the two are not equivalent, but we have an interesting counterpoint. While I'm sure performance is heavily weighted in favour of native, it seems like it's certainly surmountable.
[1] https://twitter.com/id_aa_carmack/status/695013979807047680?...
My theory on Slack's ridiculous CPU use is animated graphics. If some of those are on the screen the CPU use is at least 10%.
My theory is that their code is shit. It shouldn't be surprising given that their Chief Architect wrote a Medium post (Oct 2016) in which he cited concurrency as one of the primary benefits of PHP, and advocated for "curl'ing to localhost" to achieve parallelism.
To be honest though, since my VS Code instance is sitting at ~500 MB (all processes together) and 0%, I'd wager it's not actually Electron itself that's at fault. It probably is incredibly inefficient compared to pure native code, and probably makes it easy to write inefficient code, but still, that's quite heavy usage you're referring to.