I really don't think the problem is related to how many of an individual item you have, but how many different items you have had.
Like you could have 10 million logs, and the game wouldn't care.
But if you have (or have ever had) 1 each of 300 different resources, it keeps it all in it's memory, even if you later sell them all off and make the quantities zero.
At least that's my take on it.
Indeed [img]<fileStore.core_Emoticons>/emoticons/smile.png[/img]/emoticons/smile@2x.png 2x" title=":)" width="20" />
What we'd need is Luke to go over his code and add a kind of check at every few years or every change of year to remove from the inventory list any item you currently have 0 of in your town. You'd get rid of any kind of food you bought once at the start and then never made again, old rough tools, starting potatoes, firewood/bundles if you've switched to coal and random stuff like that from the list. If you're producing a wide range of stuff you'd still get issues from a bloated inventory, but at least you'd remove a bit of useless empty items on the lists.
I know I'd gladly accept a pause of a couple of seconds at every change of year if it meant a cleaner inventory.
(Even better would be the addition of a clean-up button that you could hit once you find yourself with lots of stuff at 0. You could skip the cleaning if your computer has no trouble with anything, or hit it as often as you need to.)