An exciting tale about what happens when you max out your asymmetric upload.

A few weeks ago I decided to enable iCloud Photo Library and start using Photos for OS X. In the past, I’ve had a patchy history with Apple’s cloud services, especially the ones that shuffle photos from your device to your “real” computer and vice versa. After enabling the iCloud Photo Library on my phone and desktop, my internet connection crawled to a halt. I was uploading photos to Apple at a good clip, but nothing else worked. In the entire house. We couldn’t stream Netflix, couldn’t load reddit and couldn’t use FaceTime while on WiFi. What had happened: due to the asymmetrical nature of most residential internet connections, the upload connection was saturated with photo uploads. This prevented any other inbound connection from ack’ing traffic to it’s source, which in plain terms meant nothing else worked.

Luckily, I run a decent router, so I was able to put traffic limiting in place, and put in rules that no host could use more than 3mbps of the 5.5mbps we get from our provider. This kept part of the upstream open, and life went back to normal. Until last night, when I turned on iCloud Photo Library for my wife. And then imported a large chunk of photos from the DSLR on my computer. Each computer happily started using 3mbps of the connection, and all other traffic became unreasonably slow – bordering on failure conditions again.

As I love data, here’s the graph of my connection, and it’s pretty clear when I started my DSLR import/upload and when I updated the traffic limiter:

Inside Photos for OS X, the only control you have is “Disable uploads for 24 hours”. Which is another way of saying “Please wait until this time tomorrow to destroy my connection once again.” I like iCloud Photo Library and Photos for OS X… but Apple needs to address this. A simple internal rate limiter, like the ones used by every other cloud sync or cloud backup provider would be sufficient.