ar71xx-master-r11827-f8424b1b26-20191228
The recent ubus version upgrade two days ago caused a bug for system log, which bug has now been fixed. However, the change also caused some services not to start, e.g. collectd (= LuCI statistics) and nlbwmon. ldir figured out that those fail where the procd init file has a "nice" parameter definition:
I have implemented that workaround in my own build.
Hopefully the underlying bug (in ubus or procd) gets fixed, but until then the workaround is to have the nice definition before the command definition in the procd init file of a service. (Note that the bug may affect also other packages/services that define "nice", but those two are the main affected ones in my build.)
EDIT:
ath79-master-r11829-e3e939d8e6-20191228
The bug (that was in blobmsg handling in libubox) has been fixed.