Account data transfer between iOS devices extremely slow

[neuhaus]

• I have searched open and closed issues for duplicates
• I am submitting a bug report for existing functionality that does not work as intended
• This isn't a feature request or a discussion topic

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Bug description

The transfer of Signal account between two iOS devices takes too long.

Steps to reproduce

• Initiate account transfer between two iOS devices
• transfer takes several hours
• when someones calls you, the transfer gets interrupted and has to be restarted.

Actual result: Describe here what happens after you run the steps above (i.e. the buggy behaviour)
The transfer takes several hours.

Expected result:
The transfer should be adequately fast.
I have 7 GB of Signal data. I have Wifi with more than 200mbit/s speed. Even if you divide that by half it should take less than 10 minutes instead of 3+ hours.

Screenshots

Device info

Device: iPhone 13 and iPhone SE 2020

iOS version: 16.6

Signal version: 6.36

Link to debug log

n/a

[philmtd]

Same issue here. In the end, I resigned and just set it up without a backup, losing all message and media history. Super frustrating experience.

[Miguel-Signal]

Hi @neuhaus

If you are still experiencing this could you reach out to support@signal.org and reference this Github issue?

[dulnan]

I'm also experiencing this right now. Transfer between old and new iPhone is running since 4 hours and is currently at 73%.

I can understand that it might take long. For me personally it would have helped if there was a rough estimate at the beginning. If I knew it'd take this long I would have done it overnight.

[karbak]

Just another data point - ~4 GB of data took just over an hour to transfer between the current version of Signal running on an iPhone 11 (iOS 16.6) and iPhone 15 (iOS 17.0.2) sitting right next to each other on the same Wifi 6 wireless network with the access point in the same room. The first time I tried this, when I clicked on a notification on one of the phones with about 50% of the transfer completed, the transfer aborted, and I was forced to start over.

[skalarproduktraum]

I can confirm this behaviour as well, when transferring data between an iPhone 12 and an iPhone 15 Pro, both running iOS 17.0.2. The amount of data to be transferred is about 10 GiB, for which Signal anticipates 3h. The transfer already got interrupted once at 50% and had to be started over.

The user experience would be tremendously better if:

• transfers could be resumed
• as most people are likely running this on a phone, it'd be great if taking a call would not immediately cancel the transfer. A notification to switch back to Signal would be helpful if the transfer is allowed to run in the background for a limited amount of time

[haloeight]

+1 to this problem. Transferring from an iPhone 14 PM to 15 PM, the transfer time goes for 3-4 hours and then fails between 39-67%, requiring application or device restart, failing again. So right now this is blocking me from using my phone for over a day. Even with the encryption overhead Apple does manage to transfer all other device data / configuration faster than Signal does.

[MalEbenSo]

+1. My transfer took 2.5h for ca. 10 GB

Transfer had good conditions: Modern iPhones with direct access to WiFi, close proximities, no obstacles, no disturbance from neighbors, Wifi in other instances uses 500-700 Mbit/s.

Unless I screwed my math, the above transfer is 4 GB/h or 32 Gbit/h or around 9 Mbit/s. Ouch!

[chingham]

+1 So damn slow...

Considering the speed of my network, the fact that both phones are quite recent (iPhone 13 Pro -> iPhone 15 Pro), and the data transfered, I would expect the process to be maximum 2 minutes long, not 2 hours...

This is really raging, especially since we cannot do anything else during the transfer with both phones, not even switch app or accidently lock the screen... Or the transfer is simply cancelled and we have to start all over again !

[jzielke84]

Yeah having the same thing right now. This is not a feature, it's a joke.

[Flexusma]

Same issue here, waiting about 1h for the transfer to complete (2-4gb chat size) (iphone 12->14) both using the latest version of signal

[hoechenberger]

I just ran into this issue moving from my iPhone XR to a 13 Pro. It's been running for 1h and estimates it will take another 10, for about 10 GB of data – progress is at 4% now. In the beginning I accidentally locked the phone and the transfer was aborted. It's an extremely frustrating experience.

[vinnyoflegend]

I'm not sure if this will help anyone as I was seeing similar issues as reported here even though my chat data is insignificant at about 500MB.

I was transferring from an iPhone SE2 to SE3 (both on IOS 17.1.x) Signal was estimating 16-30 minutes but failing to move past 0% most of the time. I tried device restarts, quitting apps, flipping airplane mode on/off, etc.

On one attempt where I was able to kick it off, it got to 99% in 20 minutes and never completed after waiting 30 minutes.

Just now, I kicked off an attempt where I directly laid one phone on top of the other as soon as it presented the TX/RX screens on each. Laying the devices on top of each other triggered the NFC/Airdrop linking (in case that's relevant). Progress started and fully completed within 3 minutes.

[st4tic-rr]

I'm not sure if this will help anyone as I was seeing similar issues as reported here even though my chat data is insignificant at about 500MB.

I was transferring from an iPhone SE2 to SE3 (both on IOS 17.1.x) Signal was estimating 16-30 minutes but failing to move past 0% most of the time. I tried device restarts, quitting apps, flipping airplane mode on/off, etc.

On one attempt where I was able to kick it off, it got to 99% in 20 minutes and never completed after waiting 30 minutes.

Just now, I kicked off an attempt where I directly laid one phone on top of the other as soon as it presented the TX/RX screens on each. Laying the devices on top of each other triggered the NFC/Airdrop linking (in case that's relevant). Progress started and fully completed within 3 minutes.

Can confirm, placing the two phones directly on top of each other makes the transfer substantially faster. I did this half way through mine and the estimated time halved from 1+ hours to 40 or so minutes for a large amount of data. Would be nice to see this included in Signal's documentation for the transfer process. Thanks for the advice @vinnyoflegend! Just saved me another hour or so of waiting :)

[notpeter]

An additional anecdotal piece of data: Transferring history between two iPhone SE3 devices was unbearably slow and after multiple attempts did not succeeded. This is especially problematic because this wasn't a device upgrade, where I had phones at home and could just leave them plugged in overnight. It was a hardware replacement (button failure) so I've been sitting in an Apple store for many hours waiting trying to transfer my data. After more than 4 hours and two interrupted transfers I gave up and was forced to abandon my message history.

I think it's probably worth creating some additional issues in addition to this one about "slowness".

• Investigate causes of transfer failure
• Feature: resumable data transfer
• Feature: move between phones without transferring message history.

I don't know if Signal Foundation does bounties, but after wasting many hours and ultimately triggering a safety number change with all my contacts and group threads, I would personally fund work on this so others have a better experience.

[zubko]

Super slow transfer as well.

As for me I don't care about transferring images or videos - it would be great to be able to choose to transfer just chats and the text history.

[Orava2]

+1. My transfer took 2.5h for ca. 10 GB

Transfer had good conditions: Modern iPhones with direct access to WiFi, close proximities, no obstacles, no disturbance from neighbors, Wifi in other instances uses 500-700 Mbit/s.

Unless I screwed my math, the above transfer is 4 GB/h or 32 Gbit/h or around 9 Mbit/s. Ouch!

I'm currently transferring data. I'm at 5 % and ETA is 4 hours. My WiFi access point shows 0 Mbps so I think that the data is transferred over Bluetooth.

[sgreadly]

You're all lucky. I had about 30GB+ to transfer due to some bug that doesn't delete older media. It wanted a few days to transfer. A few days where I have to keep both phones next to each other and not touch or use them else it fails.

Cat jumped and somehow closed the screen after a day. I gave up.

[anoxi]

I'm not sure if this will help anyone as I was seeing similar issues as reported here even though my chat data is insignificant at about 500MB.

I was transferring from an iPhone SE2 to SE3 (both on IOS 17.1.x) Signal was estimating 16-30 minutes but failing to move past 0% most of the time. I tried device restarts, quitting apps, flipping airplane mode on/off, etc.

On one attempt where I was able to kick it off, it got to 99% in 20 minutes and never completed after waiting 30 minutes.

Just now, I kicked off an attempt where I directly laid one phone on top of the other as soon as it presented the TX/RX screens on each. Laying the devices on top of each other triggered the NFC/Airdrop linking (in case that's relevant). Progress started and fully completed within 3 minutes.

Don’t know if this helped much since the transfer still takes about an hour for me.

Anyone from signal looking into this?

I guess a lot of people just give up during the long transfer, start with a new profile and accept the data loss, which is a sad experience on iOS.

[chingham]

Tbh I really think nobody at signal is even interested
Almost a year since this issue has been opened and not a single answer explaining why or giving a solution
Signal is updated once a week and yet real issues are never addressed…

[MalEbenSo]

I got my new iPad and – sadly as expected – the transfer of Signal messages took longer than the transfer of everything else.

Around 13 hours for 13 GB.
Unless my math fails me 1 GB/hour translates to 291 KB/s or 2330 Mb/s.

The devices were right next to each other. I also tried to stack them on top of each other, as somebody mentioned that this might speed things up by using NFC communication.

Frankly, I should not have to transfer data at all. I want to keep data in my iCloud account, one data store for all devices, automatically in sync. That's for iOS, but other cloud storage should be possible, e. g. company private clouds for professional users.
I am happy with (i. e. I trust) Apple's so-called "Advanced Data Protection".
Optionally Signal could offer to encrypt the data store. But really optionally, because Signal's E2EE-responsibility ends once I can see, copy, download messages.
Then the whole issue of slow data transfer becomes irrelevant.