I used to have no issues with this, but all of a sudden sysmond is using 100% CPU while I have Activity Monitor set to the Memory tab. sysmond runs normally while in any other tab (CPU, Energy, Disk, Network). The problem only occurs on the Memory tab. Turning down the update interval does nothing. I've already restarted and had no other apps open except AM but nothing changes. It still uses 100% while I'm on the memory page. I am using macOS 10.14.6, on a MacBook Pro.
My first triage step would be to make a totally new user account and isolate if you can reproduce this on a new account.
My guess is you have a system corruption or just some poorly behaving programs. Logging out of your current account after making a new admin user will let you know for sure which avenue to persue.
Without a little fault isolation and troubleshooting - people are going to just start guessing with their favorite “cure / quick fix” so I’d recommend one triage step and perhaps a follow on question once you know a clean user can spike the system and post all the processes you have in a screen shot on that new account.