By the way, did you see in adb why sharing the logs didn’t work? Either when turning the log feature on or when actually sharing.
I never used adb. I ‘solved’ it my restarting DAVx⁵ before logging, as then it always worked.
I’m running owncloud 10.0.0.4 on a slow system and requesting a contact sync >450 entries (with pictures).
As far as i’m able to judge the client is requesting the whole addressbook and after timeout exception it want to retry a request of 10 entries. At this time the server is still running at 100% cpu duty collecting the previous request.
That leads to a bunch of apache instances on server-side which freezes the system for a couple of minutes and the client isn’t getting it’s requests within it’s (too short and unconfigurable) timeout.
For reference: setting the timeout to 180sec would very likely fix this problem