I have been using Backblaze’s $5 per month unlimited and automated backup solution for almost two years and have been pretty happy with it. There are a few features I wish it had, such as more fine tuning of upload throttle — I’d like to set it to nine or 10 mbps, but the top two options are 5 or unlimited — and an easier way to see what has been backed up so far. But these are minor and really only applicable when first starting out.

Well, this is one of those times. I recently reformatted my MacBook Pro to try to sort out some of its problems. I also rearranged my external hard drives since I don’t want to take my 5 bay Drobo to Japan. I bought a 1GB SSD and a 4TB regular hard drive and allocated the data I could fit between them. Even utilizing Backblaze’s “Transfer Backup State” feature, I somehow still found myself with almost two terabytes to upload.

That isn’t the end of the world, and I’m hoping to get most of it uploaded before I leave for Japan, and before my 30 day window expires after which I wouldn’t be able to retrieve the previously uploaded files that haven’t gotten reuploaded yet. So I’ve been uploading as much as possible, except I keep finding the Backblaze client is paused, not uploading a thing.

Backblaze paused

I check the event log inside the client and find a ton of messages like:

2014-01-16 12:20:25 - STARTBACKUP
2014-01-16 13:55:54 - INTERRUPTED_BACKUP: Backed up 230 FILES / 3013 MB
2014-01-16 13:59:59 - STARTBACKUP
2014-01-16 14:13:52 - INTERRUPTED_BACKUP: Backed up 329 FILES / 471 MB
2014-01-16 15:09:39 - STARTBACKUP
2014-01-16 15:12:46 - INTERRUPTED_BACKUP: Backed up 406 FILES / 183 MB
2014-01-16 15:33:52 - STARTBACKUP
2014-01-16 15:34:16 - INTERRUPTED_BACKUP: Backed up 0 FILES / 0 KB
2014-01-16 15:36:03 - STARTBACKUP
2014-01-16 15:53:11 - INTERRUPTED_BACKUP: Backed up 343 FILES / 1061 MB
2014-01-16 15:58:08 - STARTBACKUP
2014-01-16 16:21:05 - INTERRUPTED_BACKUP: Backed up 15 FILES / 2398 MB

Backblaze interrupted

I opened Activity Monitor and switched to the network tab to see if anything else was using too much bandwidth. And sure enough, I found the culprit. Surprisingly, I found Spotify is uploading tons of data, more than Backblaze. I don’t know why OSX decides to let Spotify use all the bandwidth it wants to chokes out Backblaze to the point Backblaze thinks I am not connected to the Internet and decides to hold off trying to two hours at a time, but I decided to put a stop to it.

I opened System Preferences, clicked “Security & Privacy,” clicked the “Firewall” section, clicked the lock to make changes, clicked “Firewall Options…”, clicked the “+” sign, and added Spotify with a block order.

Spotify blocked by firewall

Then I Googled “Why is Spotify uploading so much data” and was astonished to find mentioned in the first result, “ Why is Spotify chugging upload bandwidth when it is not streaming and why does it do that at all?,” a claim that Spotify is actually peer to peer software.

A little more searching and it was confirmed. I found an interesting article detailing the functionality, “Spotify Technology: How Spotify Works.”

So there you have it. I had no idea all this time I’ve been paying $10 a month for Spotify, mostly to listen to the same cached tracks over and over, I have been unknowingly uploading probably terabytes of data to fellow users and strangling other computers on my network.

I wish the P2P nature of Spotify were more transparent. There should certainly be controls to prevent the software from using the entire available connection, especially when the client is not downloading much music itself. I could understand implementing a ratio system like other P2P networks. Then there is a whole debate to be had about whether paying customers — “premium” users like me — should have to participate at all.

Overall, I feel left out of the conversation, as Spotify is not very forthcoming about how it uses your connection. The only mention I can find in their help documents is a question “How much disk space and bandwidth does Spotify use?” where it states without answering the question:

To reduce download data, increase the cache size. To reduce upload data, reduce the cache size.

Or, just block Spotify from uploading and leave your cache alone, and Spotify will respond much faster and allow your household to enjoy the Internet again. And Backblaze can resume uploading my data. :-)