system.log flooded with xpcproxy errors during sleep time. How do I diagnose? A few weeks ago my Macbook Pro 2018 with Catalina 10.15.2 started to get mad during sleep-time, actually it's not really going to sleep as it's flooding the system.log with hundreds of these lines:

Jan 28 14:11:37 MecBucPro-2 xpcproxy[35888]: libcoreservices: _dirhelper_userdir: 557: bootstrap_look_up returned (ipc/send) invalid destination port
Jan 28 14:11:37 MecBucPro-2 xpcproxy[35889]: libcoreservices: _dirhelper_userdir: 557: bootstrap_look_up returned (ipc/send) invalid destination port
Jan 28 14:11:37 MecBucPro-2 xpcproxy[35890]: libcoreservices: _dirhelper_userdir: 557: bootstrap_look_up returned (ipc/send) invalid destination port


I'm pretty sure it could be a driver, maybe the Wacom tablet driver which was updated recently, but I am not sure. 

The only thing I'm sure is the Macbook is sleeping fine when disconnected from everything, while connected to display+hub+dock goes crazy.

Any further ways to diagnose this? 

The number in brackets "xpcproxy[XXXXXXX]" is a process ID? In this case how to investigate this process as there are thousands in sequence??
Further investigation: wake-up loop was due to a bad USB hub chain which probably makes Catalina go mad (but worked with Mojave). Reconnected 2 hubs and a Thunderbolt dock in a different order and solved it.

Anyway the xpcproxy error is there at every wake-up but at least not in constant loop.