Sorry, my answer was a response to "jacob.salmela": "This is solved in v3.2.1, which was released today." It corresponds to This.
Nevertheless I've changed the updatecheck to once a day.
I hope that this change won't have negative consequences.
3.2.1 was released in 2017.
You could consider updating to Pi-hole's most recent release.
I think what QuoVadis might be getting at is that even in the current release, there is still a cron job that does this every 10 mins:
# Pi-hole: Grab local version and branch every 10 minutes
*/10 * * * * root PATH="$PATH:/usr/sbin:/usr/local/bin/" pihole updatechecker local
While it is just reading the local version from the git repos, it does still write a file to disk, /etc/pihole/localbranches. This seems a bit more than would be strictly required if the remote version is only grabbed once a day.
I believe that updates the file with the local installed version so the web interface can display the proper information about what is installed. If you did a pihole -up without that cron job (or with the job running once a day) then you'd have a day before the web interface footer updated with the version information of the local repositories.
Edit: Since there isn't a state storage for the web interface we'd have to run a local version check every time you loaded a page if there wasn't that file to pull the information from. And that would be even more intensive on resource usage.
I think I traced that down once. Could pihole -up not force a run of that? Otherwise on a regular system, every 10 mins when nothing has changed seems frequent. This is especially true when one doesn't visit the web interface all that often. FWIW, I haven't changed mine. I'm just playing devil's advocate here.
Here are some details of my installation:
Hardware: Raspberry pi 3b+ (Armv7l), 32 GB SD-Card
OS: Debian 10 (Buster)
Pihole version:
log2ram
Thank you. I´ve changed the cronjob for updatechecker back to every 10 minutes.