What's new in this kernel update? That's a Q I have.
I just did update from 25.7.3_7 to 25.7.5, no issues with updating.
I noticed my ram usage went from 10% to 20%, disk stayed the same at 1%. Not sure if that means the 25.7.3_7 was somewhat broken (some service not working right), or if the 25.7.5 is using more than normal.
Down in the lower versions of 25.7.3 there was a point where my mem usage showed like 40% and disk was like 60%, but after one upgrade from there mem usage was low again and disk went back to 1%.
I cannot ascertain the reasons why, but just noting my observations. No configuration changes at all, just updates.
Normally I love when ram I have used money on is actually in use, and not staying idle.
RAM is used for a lot of caching of data, so RAM usage is normally not a problem, at least in the low numbers you mention here.
Basically all the commits from October 6 and 7 listed here https://github.com/opnsense/src/commits/85edba454cf9179f8a9aea0902882833d3a28c94/
PS: RAM usage may be affected by https://github.com/opnsense/core/issues/9110