Lots of "No cache entry found for..." debug messages in log

Nextcloud version: 15.0.7
Operating system and version: Debian 8.8
nginx version: 1.12.1
PHP version: 7.1.5

Hi. Since upgrading from nextcloud 14.0.~6 (can’t remember minor version) to 15.0.7, I’m getting heaps of debug messages saying “No cache entry found for…” during sync activity. Syncing is working fine, so maybe there isn’t an issue, but I don’t remember seeing it previously. Log is chock full of these.

Would be great to know if this is normal or indicates an issue.