So I started a thread in Mac Troubleshooting regarding RAM usage in tech forums here for Hearthstone. Have a computer usage monitor that monitors RAM usage and other things and been finding that the RAM on a Mac 2011 High Sierra is being used up very heavily. From 12.1 Gigs to 8.89 gigs when playing and not playing Hearthstone.
During that thread discussions I was running various scenarios on this Mac trying to figure out if it was the game or if it was something else. Did the last part of the Mac testing after June when I left the last message to September…not every day but when I had time.
Come to find out its the Battlenet desktop app that is doing this. I know it is the Battlnet.app desktop app that is doing this because the RAM completely frees up by itself after I logout and quit the Battle.net desktop app and wait three minutes the RAM is completely back to its original size ! Never fails !
The problem I have now is not knowing specifically where the issue is that the Battlenet.app desktop app is using the RAM? What function is this providing? I can free up the RAM with a tool…but this doesn’t resolve the issue of why its doing it. When I leave the Hearthstone game and cleaned up the RAM and do nothing for a while…I’ve actually seen the RAM slowly being used over time. This is really strange and am wondering is it some sort of data packet in the data folder that is doing this for Battlenet.app desktop ? Or is it some telemetry application? I’m not a programmer so trying to tear into it is not my thing. But it is annoying and shouldn’t be happening. On a PC its fine. Its just on this Mac that its an issue and its really weird. Come short of reformatting the drive and reloading HighSierra…What options do we have?
this sound like a topic for the techincal support
K. TY for your response. 
I don’t know if this will work, but I amended the edit on the location of the post and moved it to Mac Tech Support. So I hope they can look at it here…hoping I don’t have to repost this question/concern.
OrcanMutt,
Late reply, but I don’t think there’s anything inherently wrong with you using that much RAM. The battle.net application does have some types of telemetry running. If you’re running into issues with Hearthstone itself, that’s probably the game client simply caching information as you play. Especially if you’re using deck tracker apps, the game will keep some information in your RAM to make load times and animations quicker as you see/play cards and such.
To clarify, if you have JUST Hearthstone running, and NOT the Battle.net application, does the RAM usage still increase to high levels, or do you only see the increase while running the Battle.net application and the game?
Apologies for late response.
I tried running Hearthstone by itself but the battlenet app pushes itself to load when I tried running hearthstone via the hearthstone shortcut. So with the latest update on battlenet app it just won’t let me run hearthstone by itself. If I close the battlenet app after I started the game for hearthstone, the game will still play, but battlenet app still runs in background, and when I log out of hearthstone then battlenet app and hearthstone are completely shut down which is fine. I Don’t run deck trackers. Found them unstable for mac. They’re more stable on pc’s I guess. But yah, the RAM usage still unchanged. So like you said probably game telemetry stuff.
OrcanMutt,
Oh, I was not expecting a reply for this! Hey again!
There’s a setting in the battle.net application that will fully close the application after you launch hearthstone. If you open the settings to the right of the play button, you can go to the App options from the top left and choose On Game Launch > Exit Battle.net Completely just to rule it out. Other than that, if you do have performance issues your best bet would be to restart the app/game when they come up, but other than that and suggesting reporting a possible battle.net bug at the application’s forums there’s not much else I can provide for you here.