How to Fix Stuck iCloud Syncing on macOS - Part 2

This is a continuation of my original blog post on this topic. To summarize, a process called bird runs in the background and takes care of iCloud file syncing back and forth. You can try and kill this process using Activity Monitor, which might or might not solve the issue entirely.

In this part of my investigation, I will provide a few more steps to inspect what is happening. Those are a little more advanced, and while they should be safe and straightforward, I advise anyone to proceed with causation in case they don’t have a more profound technical background.

Inspecting the process logs #

All good? Let’s open up a Terminal (my favorite one is iTerm 2, by the way)

Inspect the logs for the bird process:

log show --predicate 'process == "bird"' --last 1h
# you ca set the interval as you like - 1m, 5m, 2h, etc.

The log may be too much for you to grasp directly on the command line. It may be a good idea to dump into a log file, and process with your favorite editor:

log show --predicate 'process == "bird"' --last 1h > bird_log.txt

Or, you can grep for suspicious logs right away, like this:

log show --predicate 'process == "bird"' --last 1h |grep error

For instance, in my case, the iCloud file synchronization often seems to fail because of a thumbnail generation service that fails at generating a thumbnail. I have yet to dig more about this particular part and, perhaps, write a part 3 of this series. In any case, this may likely be a different issue on your end.

Stopping all bird processes at once, using the command line #

While you should be able to do the same using Activity Monitor, I presume that manually stopping all running bird processes one at a time may result in a time gap in which a new one gets spawned. This could be a part of the issue, as the new one will start at a time when the previous one might still be holding on to some mutually shared resources (it is just my theory). Thus, I have found it more effective to stop all bird processes at once using the command line:

killall bird

I know, I know, I sense the cruelness of having to kill all birds at the same time. 🙈