People need to restart there servers every 4 hours instead of leaving them on infinite map time or some ridiculous number. The longer a server is up the worse it feels. Pretty certain TF2 has a memory leak or 5.

I agree that that is probably part of the problem, but it appears to be somewhat clientside as anyone i've asked has said they don't have the same problem

are they on the same server at the same time as you

just tested this with a friend, we appear to get different individual amounts of input lag on each server.
to specify about the lag, it mostly feels more like additional ping than input lag of movement or mouse movement.

There's a thing when you play on a UGC config that forces 'cl_interp 0'. I don't know on which kind of servers you're playing on but it might be something like this. For example, you have cl_interp 1 and cl_interp_ratio 2 and the server changes cl_interp to 0 and then it feels weird.

You should also specify your ping with net_graph 4, check if you're getting any choke or loss as well and compare that with your friend. It's difficult to say what it is when you're just expressing how it feels.

I'm pretty sure it just has to do with the float used for measuring world time in seconds just becoming inaccurate over time. Either way, you're right, changing the map after an hour or so will prevent this sort of behavior. I find skial servers almost unplayable because they've usually been running for like 9 hours.

if u use an fps limit remove it with fps_max 0