Abnormally high CPU usage on web UI on OPNsense 25.1.9_2-amd64

[brianbaggs@hotmail.com]

Hello,

I have been using OPNsense for a little over a year now. I am using a mini-PC that is made for the purpose of being a router. It has 4 Intel I226-V ethernet ports, an Intel N100 CPU, 16GB of DDR5 ram, and a 512GB NVMe SSD. For the first year or so everything ran great and I was very happy with it, but ever since upgrading a few months ago, I am having an issue with the web UI.

Anytime I log into the web UI, the CPU utilization maxes out at 100% and stays there. As long as I'm not on the web UI, everything works great, but as soon as I login to the web UI, the CPU just starts maxing out. I ran top and saw that the problem was coming from php and php-cgi.

So I am wondering if anyone else has had a similar issue and was able to fix it? If so, I'd really appreciate it if anyone can share a way to remediate this issue. I checked the logs and I'm not seeing any errors or anything. Re-installing OPNsense is my last resort because I don't really want to do that.

Thank you.

[Ilya Nazarov]

I have the same issue with the same symptoms on my HA backup appliance. The master is ok. Release version is like yours and I updated to it right after having both servers installed. Both appliances run on VMWare.

Did you find anything so far? What version did you use before upgrading?

[brianbaggs@hotmail.com]

I have the same issue with the same symptoms on my HA backup appliance. The master is ok. Release version is like yours and I updated to it right after having both servers installed. Both appliances run on VMWare.

Did you find anything so far? What version did you use before upgrading?

Hello,

Unfortunately, I did not yet find a solution. I saw one post that said deleting the /var/lib/php/sessions directory could fix it, but I tried that and it did not fix it. I was using whatever the last version 24 was before they upgraded to version 25. I don't think this issue started right away after updating, so I have no idea what could be causing it. If I am not logged into the web UI, everything runs perfectly. When I log into the web UI, that is when things start getting hairy. I can see the load averages are normal but when I log into the web UI they start getting very high and my monit instance starts sending me alerts because of it.

Anyone out there have any solutions for this? I really don't want to have to re-install the entire system because all my settings are finally setup right and working great, minus the high CPU usage when using the web UI. That is the only issue I am having at the moment. My session expiration is set to the default value and I haven't changed many settings recently. The only thing I can recall doing is disabling the Intel QuickAssist technology when I found out that the Intel N100 processor doesn't support it.

The system I run OPNsense on is a mini PC that was built for the sole purpose of using it as a router or network device. It has quite a bit of power with the Intel N100 and 16GB of DDR5 ram, and a 512GB NVMe SSD drive. The ethernet ports are Intel I226-v and I use two out of four of them. I use one for WAN and one for LAN. My LAN one goes into a smart switch that connects the Wireless access point and other wired devices and the WAN one goes out to the cable modem for my ISP.

I have been searching the web quite a bit looking for an answer but I've yet to find one. If I do find one, I will come back and make sure to share it.

[Ilya Nazarov]

During investigation I found a bug with config.xml being blown up on HA sync: https://github.com/opnsense/core/issues/8911
I'm not sure if that was the reason of high cpu, but I had to reinstall the backup. After that, the cpu and mem load got normal.

Just in case, check if your config.xml is bloated.