My response times were getting very slow - especially from my Lutron Pico devices (which if they performed well I'd be in love with). So I got a second hub - decided to make that the server. Thanks to great documentation and video by @csteele I got up and running. I connected my devices and see them mirrored to the the server.
From what I've read I want to separate the zigbee devices, at a minimum, from the others, and then even turn off the Zigbee antenna. Is that right?
So do I need to delete them entirely from my original (now remote) hub and then re-add them through device discovery on the new server hub?
Or is there some other first performance step I should take?
I have a total of 60 devices in my Device tab. That includes z-wave and zigbee - with sonos, lutron Picos, Hue, and Ring devices in the mix.
Edit: Since I marked @Tim-in-Ca post as the solution, I wanted to highlight that it was the Lutron Pro Reboot that did it. All the other stuff will be a future experiment.
You don't have to separate your z-wave and zigbee devices. I have all Xiaomi-compatible zigbee devices on one HE (zigbee channel 25) and my other zigbee & z-wave devices on the other HE (zigbee channel 20).
I put some of my cloud integrations (MyQ, SleepIQ) on ST.
When you're planning the distribution of your devices, unless you have a large quantity of each type, I recommend keeping all of your Zigbee togther and all of your Z-Wave devices together so you do not run the risk of weakening either mesh.
They don't have to live on the same hub, in other words, Zigbee on one hub, Z-Wave on the other.. But with 60 devices I woudn't worry about that.
This is where I would go if I was the OP. Have one hub for all of your local devices.. On that hub I would put my rules that control only those local devices. On my server hub I would place all of the LAN and cloud integrations and dashboards, and share all of the devices from the remote hub onto the server so I could use them all for dashboards, rules, etc.
The benefit of this approach is that if the server hub dies, or gets slowed down by a LAN integration, or runaway driver due to a cloud outage, all of your local mesh devices and rule continue to chug along unaffected.
There are a lot of right answers on ways to deploy HubConnect and very few wrong ones. This is just another way.
I use Lutron Picos (along with many Lutron switches), Lightify, Sengled, EcoLink bulbs, Iris V2 motion sensors, Samsung leak/motion sensors for ZigBee. Zwave-wise I'm using 2x Quikset locks, 2 GE dimmers as well as a Dome shut off valve. I ever only experienced one hub slowdown, but did suffer from Lightify instability. For now, I've moved my problematic LIghtify's over to the 2nd hub. Picos and Lutron Switches have never been problematic for me. On the 2nd hub, I did disable Zwave. If I start experiencing slow down issues, I'll probably start to load balance between the two. As a test, have you tried to reboot your Lutron Pro hub?
That was exactly my calculations a short while ago, when I moved from one hub to 2 hubitat hubs, and I brought out my old SmartThings from the closet!
I put all my devices (Zwave + Zigbee+ Lutron) on the remote hub, and all my rules on the server. I also put a shadow copy of all my devices on SmartThings as the source for Sharptools and other Internet stuff. Very easy to do, and surprisingly fast and responsive (due to the relative speed of an ethernet connection versus the speed of local zwave/zigbee actions).
(On my server hub, both the zwave and zigbee radios are disabled).
As the master @srwhite says, "there are many roads to nirvana".
P.S. I personally think that one of the reasons that Hubitat hubs are slowing down is because the zwave radio/log cannot handle "many" devices at the same time. It's entirely possible (in my humble opinion), that a "good night" routine (of "many" zwave devices) will overload your hub. I just don't know, and perhaps the latest firmware will address that issue.
As a test, have you tried to reboot your Lutron Pro hub?
Ok. Now I feel stupid. Rebooted Lutron Pro hub and response time went from something like 10 seconds to 0.5. Anyone want to buy a very slightly used Hubitat hub? Nah.... now that I got it, have to have fun reconfiguring everything!