iCloud Photo Library upload killing internet connection

The following will address the issue for many users until Apple makes a real fix. This fix limits the upload speed from your computer. It appears that some ISPs (mine is Comcast) heavily throttle your connection if your computer is hitting the limit. I've been running limited at 80% upload speed for 24 hours with no problem.

This fix is easy but a bit geeky. You will use Apple's Network Link Conditioner (NLC) system preference panel from the Apple Developer site to limit your network connection speed.

1. Download the NLC system preference from the Apple Developer's site. It is part of the Hardware IO Tools.
2. Install the NLC system preference.
3. Open the NLC system preference and create a new profile.
4. Limit the Uplink speed. I tried both 60% and 80% of my available uplink bandwidth and they seemed to work OK.
5. Set the Downlink limit to something at least close to your ISP's bandwidth or above.

You'll probably need to play around with the limits. Remember that it affects all of the network traffic in and out of the computer so something like a Time Capsule backup might go really slowly.

Here's the setting I used:

Now that's a pretty good workaround. I'll give it a shot before I throw more photos in my library tonight. i have about 20k more to go.

Thanks mayall -- definitely going to give this a shot tonight!

Thanks mayall. This workaround seems to be working for me so far. I'll check in the morning and report back. I have also seen this problem with iTunes Match when iTunes uploads songs that it cannot match. I'll be so happy if this works.

I can confirm that this workaround has fixed the issue on my Mac. Thanks again mayall.

I'm having a little trouble with the Network Link Conditioner tool -- it installed fine, and I set it to restrict my upload bandwidth to 1.0 Mbps (which would halve my TWC upload max of 2.0 Mbps). However, when I run a speed test after setting it up, I'm still getting ~2.0 Mpbs upload speeds. Any thoughts? Maybe I should try setting it to 1,000 kpbs instead, even though that should be the same thing.

Since only whole numbers are allowed, I found it more flexible to use Kbps. Using Kbps lets you enter smaller increments or a bandwidth of less then 1 Mbps. For example, I am using 3500 Kbps since you cannot enter 3.5 Mbps.

Thanks mayall -- will give it another shot this evening.

This workaround appears to help this widespread problem. If you'd like to pass along the fix, I've created a post:

How to fix Apple Photos iCloud Photo Library upload using Network Link Conditioner

My internet connection was also killed by the upload process. However, to be clear, the upload was going just fine, but the process made all other internet activities impossible for the computer, and any other device on my network. I had a 280 GB Aperture library with about 46K pictures. It took a solid week, with much pausing and resuming in the Photos prefs, to complete. I'd definitely recommend this approach rather than just resetting your modem as some have suggested.

Now that it's done, I haven't noticed any major slowdowns, but I'm guessing if I ever do a big import from a regular camera, my connection will be clobbered again. The Photos.app preferences could really use a throttle of some sort, where you can specify the max upload speed, and maybe even a time of day for the upload (like the middle of the night). Hopefully we'll see something like that in a future release.

Good luck!

Whoa! Great find. This functionality should definitely be integrated into Photos, but this a solid workaround until then.

mayall wrote:

This workaround appears to help this widespread problem. If you'd like to pass along the fix, I've created a post:

How to fix Apple Photos iCloud Photo Library upload using Network Link Conditioner

For more context, here's Walt Mossberg's review of Photos -- he appears to have had the same problem, which Apple coyly called a "rare bug" (doesn't look so rare) and seems to have attributed to Mossberg's having used multiple versions of iPhoto over the years, and something about duplicate photos.

https://recode.net/2015/04/14/review-photos-apples-replacement-for-iphoto/

I had the same VERY maddening problem that everyone else is having -- as soon as I disabled iCloud's Photos mechanism, it stopped -- and this was after multiple calls to my ISP, a new DSL modem, a new router, many many speedtest, and hours of lost time. On top of that, the Photo library didn't even finish uploading! Very weak performance on Apple's part here -- seems like they didn't test it well at all.

My ISP tech told me that the line had been saturated with upload data for weeks, which in fact *does* cause the download speed to slow to a crawl, because it's constantly being deprioritized. That made me wonder which apps were trying to upload, which led me to Photos (which, of course, wasn't even open -- it was doing something or other invisibly in the background the whole time -- nice!).

I left feedback at http://www.apple.com/feedback/.Hopefully they patch this.

lythaus wrote:

I left feedback, hopefully they patch this.

Where do you do this? Usually it's in the app menu, but I don't see it there in Photos.

Same link people are posting above: http://www.apple.com/feedback/

Then you can navigate to Photos and leave it under there.

I spent the past week troubleshooting my issues with iCloud Photo Library. It's taken a while to narrow down possible causes. But now, partially thanks to this thread, I'm convinced there are certain modems, for whatever reason, that have issues with something Apple is doing during the library upload.

The following modems have been used on my network (starting with the modem I've used for three years up to the current, working modem):

1. Arris WBM760A (Texas Instruments)
2. Technicolor TC8717C (Broadcom)
3. Ubee DDM3513 (Texas Instruments)
4. Arris/Motorola SB6141 (Texas Instruments)
5. Zoom 5341J (Broadcom)

With the WBM760A, I was having extremely high latency (>200ms; sometimes >10,000ms), packet loss (>50%), and ultimately a complete loss of traffic. The modem always recovered on its own, but this would happen every 10-30 minutes where traffic would stop for a minute or two then recover. I called Comcast support to have a tech sent out to help troubleshoot.

The Comcast tech checked the line, which tested well within working parameters. He said he was convicted the modem was at fault. The first thing he tried was to swap out my WBM760A for the TC8717C. This resulted in much better latency (<100ms) and inconsequential packet loss (<1%) during upload. However, there were unknown issues getting the modem fully activated on my line, so he went to his second choice, the DDM3513. The DDM3513 was better than the WBM760A in that it never stopped passing traffic, but latency was still high (200ms–500ms).

While the tech was working getting the modem up and running we discussed the pros and cons of renting vs. purchasing. This led me to decide to purchase, and I went with the SB6141 based on the tech's recommendation and positive reviews on the Internet. Unfortunately, it was as bad as the WBM760A and maybe even worse. Not only did traffic stop completely at times, the modem would often reboot without warning.

So, I did a little more research into what differences there might be with the one modem that worked (TC8717C) and all the others. In this thread, I noticed most of the modems listed were Arris/Motorola. Additionally, the modems listed in this thread and those I tried use a Texas Instruments (TI) chipset, except for the TC8717C which uses a Broadcom chipset. It could have been coincidence but was worth further investigation.

I decided to find a Broadcom-based modem that had good reviews and was available for retail purchase. The 5341J fit the bill perfectly, as it was highly recommended and Broadcom-based. So far, the modem is performing well. Latency is low (<100ms) and packet loss is negligible (<1%).

Hope this information helps others.