Server stability has never been perfect for the game. I'm not sure what the cause is, but one way to optimize is to handle AFK players differently. There's a very large amount of players who are logged in but are doing AFK activities while they sleep or work. I suggest some kind of low-bandwidth mode for those players. It can function like this: If a client has not received any input after 2 hours, then activate low-bandwidth mode for this client (another way to activate low-bandwidth mode is by minimizing the game). While in low-bandwidth mode, a large amount of packets won't ever get sent to the client, including packets of other players moving (maybe just make all other players invisible so they don't appear moving into walls for the client). There's some additional work needed to handle specific situations: Packets related to flagged up players should always be sent in case someone attacks the AFK player. When the client exits low-bandwidth mode, the server should send an update of all nearby players so the AFK player gets an up to date view of their surroundings as they resume playing. Don't activate low-bandwidth mode if the client is on someone's mount (two-seater horse or a sea vessel). I imagine this would drastically lower bandwidth usage for the servers. There's likely hundreds of players constantly AFK in cities training horses or fishing.
Would Kakao even be able to dynamically adjust player's bandwidth? I think it'd be simpler to make a channel for afk life skillers. Maybe even give them slightly boosted exp and reduce channel chat costs.
Pearl Abyss created the netcode, so they definitely have the capability. Adding an afk-channel would help, but that would just move the traffic to another server. Having a low-bandwidth mode for clients would remove a lot of traffic altogether.
Just turn afk players into NPC's after x time. Give people way to logout while logged in, and optimize the bandwidth and rendering for ACTIVE non npc players.
It'd actually be better to kick the AFK'ers after a certain amount of time, unfortunately BDO is a game that focuses heavily on AFK activitys. If you have ever had any server experiance you will know the less players the better (also the less conflicting objects e.g. monsters spawning in tress/underground, overlapping objects in this case boats overlapped out not put away), lower running costs, more free'd up resources. better server performance that shows client side e.t.c. OFFLINE MODE would be a better option in all ways shapes & forms, with the exception that it'd be hacked in 5mins. So they'd need to look at something like Set task/s when offline mode server side which gives them alot more options.
Kicking AFK players definitely wouldn't work. For better or worse, spending time AFK is part of the game and they'd have to do massive balance changes to the game if they're gonna remove it (for instance, expect to see virtually no horses ever get listed if AFK'ing is taken out). What Judgementos suggested would work: make AFK players invisible, and make other players invisible to them. That way, almost every packet going to/from AFK players could get skipped. The downside is that it would make the world look less lively (then again, the liveliness of AFK players tend to look ridiculous since it's one giant crowd in a tiny fishing spot, or twenty horses running back and forth down the same street). It would also make it impossible to attack AFK players -- which would be a good change in my book.
I agree, with Judgementos and you're opinion here, invisible players would fix some issue and I assume less "I woke in margoria again" super sad faced tickets to support. <<-- Oh you know they get these! If a net full of people fishing is ridiculous I guess? How about standing in a circle in the main porting city of Leadis asking people to "rub your egg" just before going AFK for the night so your dragon hatches faster/stronger/better... must be really ridiculous. But it happens, in some of the more weird places in the world.