Excessive Mobile Data usage after iOS 9 update - System Services - General

I restored my phone with a fresh 9.2.1 firmware. Unfortunately for me, I forgotten to turn off all the data related settings and my monthly data allowance of 5gb has been depleted within hours of a fresh ios restore. What puzzles me is that, in my icloud have the default 5.0gb free space but within "manage storage" I have the following:

I still don't get how my 5gb data allowance was depleted when my stored data in icloud above is around 3.85gb only. My General usage was a staggering 5.2gb.

Very interesting. I thought that I was the only one having this issue. Internet usage has been very high, as high as 100gb, yes GB not MB per day. Since turning off iCloud backup on both iPhone and iPad, usage has been back down to about 1gb per day. Have no idea what the iCloud backup is doing to consume that much data. Will need to dig deeper into it.

My daughter's 5S is having the same issue. If we turn data on for even 5 minutes, the phone burns through 100mb or more data... without opening any apps. Last month, she racked up 21.5GB and she is a light user compared to most. Running my iphone side-by-side on the same network (even the same account) produces totally normal data usage.

Where is Apple on this topic? Are we alone in the dark here?

WOW....thanks. So far, so good. Resetting the network sure seems to fix my problem. Not being a network person, I was surprised it reset my entire home network not just my phone.

Hi all,

recently I too have started to struggle with this problem, so I thought it would be useful to report my experience.

My terse answer is: the problem could be due to iCloud synchronization.

The complete reasoning follows in this post, in which I try to summarize my findings so far, accompanying them with a proper defence. I hope this helps getting rid of the problem as well as establishing or retracting the validity of several commonly suggested repair actions.

Problem statement

Excessive unintended usage of mobile data (up to ~600MB per "data session"), of course depleting my 1GB weekly plan.

Occurring on an iPhone 6 and on an iPad Air 2 (same Italian mobile operator: TIM), both using iOS 9.2.1.

The only cellular data usage counter that significantly (enormously) increased after each occurrence of such a condition is "System Services->General". Definitely none of the app-specific counters indicated unexpected amounts of consumed data.

Ruled out causes

1. It is not (just) iOS 9

I have been using iOS 9 roughly since its roll-out in Italy last september. Since then, I have performed all the released minor upgrades, up to the most recent iOS 9.2.1. Mobile data usage has always been perfectly fine and in line with my usage pattern up to about a couple of weeks ago (no iOS upgrades occurred at that time).

Therefore, I am fairly sure iOS 9 is not the (only) culprit.

2. WhatsApp automatic backups are not relevant

I have at least two reasons for concluding this.

1. I have tried to execute a manual backup of my chats while I was connected to WiFi, which is backed by an ADSL with 1Mb/s upload bandwidth. WhatsApp reported the total backup size to be 496MB, therefore it should have taken more than one hour to perform a full upload. Instead, it took just about 2 minutes, and the upload progress evidently "leaped" some chunks of data (and the corresponding percentage values). This makes me conclude that backups are incremental (i.e., only data that has changed since the last backup is uploaded to the server), which makes perfectly sense.
2. The excessive data usage problem occurs also on the iPad, where WhatsApp has never even been available as an app.

3. It is unlikely to be malicious traffic

Of course I have been thinking several times that the anomalous traffic could be triggered from the network instead of the mobile device (e.g., something like "ping storms" or any other kind of traffic coming from the mobile network and silently soliciting a response from the mobile device, or even just sent to the device without any responses expected).

However, I find it somewhat unlikely because the detailed report of my data plan usage, issued by the mobile operator, reveals that unintended bulk transfers occurred in the following conditions, which are very likely to match malicious activity patterns:

• For the iPhone, they mostly occurred at the exact times when I switched it on.
• For the iPad, they mostly occurred around midnight (consider that I turn off my access point in the evening - before midnight - and the iPad is powered on 24/7).

4. It is not the "WiFi Assist" function

I conclude this because I just keep WiFi off for most of the time on my iPhone, therefore there is no reason for cellular data to be consumed to "come to the rescue" of WiFi. In the rare cases when I use WiFi, I am usually at home with very high signal strength.

5. It is not the App Store

After resetting cellular data usage counters, I have tried to download a previously purchased app totaling around 5MB. Most of the consumed data traffic was accounted in the "App Store" entry of the "Settings->Cellular data" menu. Only less than 1 MB was reported for "System services", 0 of which for the "General" entry.

As a side note, I have always been keeping the "Use cellular data" option turned on for automatic app updates, without ever seeing any relevant data usage (I suppose the App Store self-limits when connected via cellular network). Moreover, dates of last update of the apps do not coincide with the dates for which the mobile operator's log reported abnormal data consumption, so I can reasonably assume that not even automatic app updates are involved.

Further investigation and potential cause

TCP connections

Based on the observation at point 3 above (that unintended bulk transfers occurred at the time of switching on the phone), I have tried to monitor the active TCP connections on the iPhone at boot time, immediately after the "Apple" logo disappeared. I have used the HE.NET app for this purpose. With the help of a Whois service invoked on the remote endpoint's IP of each TCP connection, I could narrow down the involved services to the following:

• Yahoo
• Dropbox
• Amazon
• Adobe
• Google
• CloudFlare
• Akamai

Most of these are justified by the presence of an associated app. Others (Akamai, CloudFlare, Adobe) are fairly generic but still apparently reasonable.

Occurrence pattern

According to the operator's cellular data usage log, the largest amounts of data have been consumed on the iPhone on a specific day of the week: Saturday. There are no special operations I accomplish on this day, especially at the time of switching on the phone and, definitely, nothing that I didn't do in the era when the problem never occurred. Unfortunately, this observation is a bit flawed considering that the same report on the iPad showed data consumption also on other days of the week.

iCloud might be relevant

So far during my experiments iCloud was the only service that caused an increase of the "System services->General" counter. The tests were pretty simple: after resetting cellular data usage counters, I have applied changes to a document in an app which synchronizes with iCloud. The app-specific data counter did not increase significantly at all, whereas the "General" counter increased by a more or less expectable amount.

Even more, in a file manager app that has access to iCloud I have tried to drop a file of a few Megabytes in the iCloud area, seeing no increase for the app-specific counter and an increase of a few Megabytes of the "General" counter.

In the end, this makes me suspect that iCloud could be the culprit. I am keeping cellular data usage for iCloud disabled in the following days. Even if this rather annoys me (since the goal of keeping everything synchronized at any time is defeated), I hope at least it will help me get rid of this very disturbing problem. Of course, the reason why this started to happen suddenly, without any updates/upgrades or configuration changes occurring between the "before" and the "after", will remain a mystery. For the moment, I can only assume that some iCloud-based app has been "inadvertently flawed".

Hope this helps you as well.

Adding a couple of considerations.

First, in my previous post I meant "iCloud Drive", not just "iCloud".

Second, the only apps that are listed as those that consume space in iCloud Drive are iMovie (less than 1KB), Goodnotes (about 150MB), and WhatsApp (taking up more than 450MB). Considering that Goodnotes usually transfers only a few KBs each time, suspects still fall on WhatsApp, which by the way has also been recently updated a couple of times. However, point 2 in my previous post as well as the fact that WhatsApp does not even exist for the iPad seem to refute this hypothesis.

However, I am unable to think of any other apps making heavy use of iCloud, since the total consumed space perfectly matches the sum of spaces of the three apps listed above.

Let's see what happens in the following days.

Update: after slightly more than one week keeping "use cellular data" for iCloud Drive disabled, both on the iPhone and on the iPad, the problem has never re-occurred. Any reported data usage was completely in line with the expected amounts, and the "General" entry among the data consumed by "System services" was definitely negligible. So, at least in my case, the problem is likely to be ascribed to cellular data usage by iCloud Drive which, as indicated in my previous posts, sums up into the "General" entry. Once again, the strange thing is that such excessive data usage has never occurred so far, even with "use cellular data" for iCloud Drive enabled.

As an additional piece of information, I have observed that cellular data usage reported by the operator is not necessarily accounted for at the time of the day when it actually occurred. Therefore, large amounts observed at midnight or at the time of power-on are likely an aggregate of the usage occurred on the previous day. This partially defeats my hypothesis #3 ("unlikely to be malicious traffic"), because hourly traffic consumption patterns are unknown at this point. I still consider this a very unlikely circumstance, though.

Still, this heavy traffic by iCloud Drive is very strange, considering that none of the 3 apps listed as users of the iCloud Drive space is supposed to perform large data transfers. There are a lot of other apps for which access to iCloud Drive is enabled, but only the aforementioned 3 are reported to consume some space (600MB in total).

Another update: It has been almost one month since I have deactivated cellular data usage by iCloud Drive and the problem has never occurred again. So, in my case, iCloud Drive was apparently the service causing high data consumption (which is not that obvious, considering all the arguments in my previous posts).

I would like to highlight that all the following supposedly "data-hungry" features have always been switched on during the test period (and indeed have always been switched on before the problem occurred):

• Weekly WhatsApp chat backups
• WiFi assist
• Cellular data usage by the App Store
• Automatic updates from the App Store
• iCloud sync (but not cellular data usage by iCloud Drive)

So, the final observation is that without cellular data usage by iCloud Drive the "General" byte counter among "System services" never increased by a noticeable amount, and overall cellular data consumption was absolutely reasonable and in line with daily usage.

Considering that several upgrades to iOS (I am now using 9.3.1) and WhatsApp (I am now using 2.16.1) have been released in the meantime, I am timidly re-enabling cellular data for iCloud Drive, in the hope that the latent problem has been fixed. I started with the iPad, and this seemed to have no adverse effects for about one week. Now I am re-enabling it also on the iPhone, bringing the setup to the original configuration I have always been using. Let's hope for the best.

I don't believe WhatsApp is necessarily the cause, at least not in my case. I have the app installed but I have no chats or any media saved via WhatsApp.

I also don't get why there are two features: iCloud and iCloud Drive where apps can save their data. Both have duplicate settings for many apps eg. you can enable/disable Safari, Mail, WhatsApp, and many more.

I had the same issue today and my phone consumed over 3 GB of data within a span of 2 hours. Upon inspection, 'General' under System Services had consumed 5.2 GB. I contacted the service provider and they were happy to reverse the additional charges as a one off. I then took screenshots of all the apps' data consumption and reset the statistics. Found this link and switched off the iCloud Drive Mobile data usage as advised. Now it seems the data drain has stopped.

Thanks to all the contributors.

P.S. It is still a mystery what triggered the sudden activity, especially when there was no change in my usage pattern.

I fully agree on the mystery of this behavior and confirm the absence of changes in usage patterns.

Apart from that, re-enabling iCloud Drive synchronization on the cellular network (all the other settings being unchanged) seems to have had no adverse effects on data consumption since my last post (about 15 days ago). So, apparently things went back to normal, possibly due to some software update occurred in the meantime.

I am having the same problem with only one of our four phones. I did find this article and will be trying many of these fixes once I get a chance. There are 18 tips to try out, so be sure to go through all of them!

You did an excellent job of analyzing potential causes of the data usage issue. Let me share some things I found. I've posted what I analyzed in other posts in this forum - Using iPhone: Battery problem after update to IOS 9.3.1, Battery Drain Solution as affected by identityservices / Messages,

Unknown email appears on iCloud restore (ios 7, iPhone 5)

My issue started with severe battery drain on my Watch - then my iPhone. My issues are fixed (at least for now). What fixed it was a DFU of my iPhone and setting it up as new - at Apple's recommendation. I also think that was somewhat extreme - and it may be a coincidence that it went away. Here are my findings/thoughts:

• Severe Battery Drain - A system task (identityservices/d) uses excessive CPU and creates the battery drain. (I used Xcode and Instruments to confirm this.)
• High Data Usage - this is another effect of the system task running very high CPU. The systems task has something to do with credentials. You will see the high data usage if you are on cell data. Although I'm sure it happens on wifi too - you would need to use an app to figure that out - there is a real good one available. The task is working on some iCloud queue and uses excessive data when trying to do so.
• "Symbiotic" relationship across most/all of iOS and OS X devices under the same Apple ID. The system task is used in OS X and iOS - and the same things are or can happen on all devices. Discovered this accidentally.
• "Break" the cycle - and it clears up battery and data usage issues.
• This issue does not seem to be tied to a specific version of iOS - if you look back in the forums - this has been happening for a while. I think it's one of those "anomalous" software errors - it happens only under rare circumstances. I don't see many people having this issue (but the post on the forum can bea tip of an iceberg).

I was able to provide a lot of data to an Apple advisor (at some higher tier) that might help them find the issue. I don't expect to hear back personally.

Hope that gives you some food for thought - and other. I do think this can pop up again - that's my big concern.

Im still having this issue. I have 6G of data per month and I've exceeded it twice. Im really starting to hate the iPhone now.

I Just tried resetting my network settings, if this does it fix it, I'm getting rid of the iPhone.