Hello, we have a guild of 500 unique users and 800 characters. we have 4 raid groups and 2 of them have overlapping schedules. When the dkp for boss kills goes out , it causes 1-3 second lag spikes for all players.

What version are you using?

2.1.2

The packets sent during dkp distribution is pretty much as minimal as possible. Perhaps I can go about throttling the applying function. But it wouldn't change too much. We'll see what can be done. Large scale rosters tend to make it a bit rougher as it has to search through the entire table to apply values to each player.

Could there be a way to apply the changes and update the tables of only the users in the raid group and then have an officer sync the changes globally after the fact?

Not without manually editing the send script, no. I can look into possibly adding an option to limit the scope of those broadcasts.

If you deem it worth while, that would be an excellent update. If you are taking external contributions I can fork it and do the work myself.