having 100,000 items stored as 100 item stacks could result in 1,000 rows in the db (item-id and qty, depending on how it’s represented). sending them down to the client is 1,000 item-ids plus qty which has an impact on bandwidth.
setting stack size to 100,000 would result in a single row pulled back from the db and a single entry sent to the client, reducing bandwidth.
i’ve been told that increasing item stack sizes does not help with performance.
Stacksize definitely -can- help. Its not automatic, as it still depends on how players use it.
I’ve had the suggestion of a specific storage not having rows and columns at all. Where you can drop 200k+ stone in say a stone storage container, and then instead of 45 or 200 slots, it effectively has a single one.
But again, it depends if players prefer to use it, if they keep dropping stone in chests, then obviously it doesn’t do anything.