I am getting complaints of major lag on my server.  The only thing that keeps popping up in the console are two things for backpack mod.

Calling 'OnPlayerLootEnd' on 'Backpacks v3.6.3' took 6783ms 

Calling 'OnEntityKill' on 'Backpacks v3.6.3' took average 6784ms 

I have uninstalled and reinstalled the mod twice already and still having these messages constantly popping up.  I don't see any messages for any other mods.

Any suggestions are welcome, I've tried so many things trying to alleviate the lag.  Thanks!

These hook warnings are often symptoms rather than causes. Meaning, the lag could be coming from anywhere. There have been no significant changes in Backpacks recently, and no other reports of this issue, so at this time, I'm inclined to think it's not caused by the Backpacks plugin.