As the Title says while having Raider.io turned on the Performance of WoW is drastically reduced. Huge FPS drops .
While hovering over the Menue button laggs occure.
tried it in a Raid with 20 people all had increased FPS after disabling Raider.io and no more stuttering. (in my case i tried it without other addons installed.)

I suspect the culprit to be an addon that calls UpdateAddOnMemoryUsage() that is also called when you hover the "computer" icon to get memory usage information.

Calling this is costly, and if an addon is using this regularly to display memory usage all the time, it will be why you have this experience.

I recommend to disable such addons or plugins, just no good idea what it might be called.

UpdateAddOnMemoryUsage() is called from blizzard itself as a "Feature" when hovering the Computer icon to show our usage that is right. To make sure nothing else could be the cause i disabled each Addon. In the end the Solution was to uninstall Raider.io. Even hovering doesnt cause laggs with Raider.io beeign Uninstalled. The Only Thing i can imagine by this point is that i have some part in my PC (probably the RAM) that causes this Bug in the End since (nearly) nobody else has it anymore. Sadly im more into coding and less into hardware x)

I also have the small freeze when I hover it, and as long as I hover it, it keeps "ticking" every few seconds causing this issue.

I am not sure why, it is a bit unfortunate, but the memory usage API is very old and when it was made, addons certainly did not come with a full database shipped, so it is probably one of those things that could get an update, maybe in the next expansion.

Sorry, I am not sure how this can be fixed if it is truly an issue that persists regardless of other addons, then it could be something else, hardware, OS, etc. causing this issue.