"Steam Helper" process has constant high CPU activity

[Simon]

A background process called "Steam Helper" has constant high CPU activity, even when all Steam windows are closed and no games are running. This is causing high temperatures, excessive fan noise and poor battery life, to name a few.

The process typically consumes up to 100% of one core and smaller amounts across several other instances; at least 10% of my 8-core i9's total power...constantly and with no windows open! It consumes more than most of the games I play. This is wholly unacceptable. My MacBook has a hard enough time trying to stay cool and quiet without having errant, rogue Steam processes to contend with.

What are they doing? I read that they're supposed to handle rendering, but they run high even when all windows are closed (even higher sometimes) or when I'm simply in a forum, where CPU usage should be very low. The app has long been terribly sluggish on Mac, which is one thing, but it's another to be hogging so much CPU when it's not even doing anything! The issue is absent on Windows.

It appears that issues with Steam Helper (and the app in general) have been common with the Mac version for years. Is Valve ever going to make a fast, modern and responsive app and launcher? Somehow I doubt it. They seem incapable and/or unwilling to do so. I doubt I can support this platform anymore unless they get their app in better shape. This issue is a total deal-breaker. Shame.

[Simon]

Some further testing reveals at least 2 serious issues with the app on macOS:

First, the app is using an ungodly amount of CPU--both during use and when simply open in the background. The app is using 2 or more cores worth of my 9th-gen Core i9 to do something as simple as write this forum post! Something is seriously wrong for it to be behaving like this. It certainly explains, but does excuse, some of the sluggishness observed. Most other pages, including the Library and Store pages, consume similar amounts.

Second, the app seems to continue rendering--and consuming the same resources as--whatever the last page you were on *after* you close its window! This is just so stupid; another cardinal sin. Occasionally, and inexplicably, the Helper processes die down and the app behaves normally, but this is rare.

I just can't comprehend why such a mega-rich multinational corporation can't find it in themselves to keep their primary product and means of generating revenue remotely current and modern on all platforms. The current (garbage) state of the app on macOS suggests that they just don't care about Mac users. This is of course not particularly surprising...Mac users are used to behaviour like this.

In the absence of Steam actually caring or doing anything about it (which is extremely unlikely) I suggest users experiencing this and who find it unacceptable to use the forums and chat through a modern browser like Safari and consider taking your game purchase business elsewhere. I can't justify having my Mac run constantly hot and loud because of the Steam app when I'm playing a low-resource game like a board game.

[insane clown pagliacchi]

I have Steam installed on my newish Macbook as well as an incredibly old and clunky i7 pc desktop and have exactly the same problems as OP. Steam NEVER takes as many resources on the pc app, even when actively running games, as it does when idle on OS X. I realize no one cares about Mac gamers which is fair enough, but I'm a customer that runs on both platforms regularly (I use both computers daily) and the Mac version is just unusable.