Reproduce
- Same SIM card with 4G, same testing location, connected to the same server, xcode debugging game applications,
network/profile retrotransmitted, Avg round tripto view data - iPhone17， Turn off 4G and turn on WiFi. All the above indicators are acceptable
- iPhone17， Turn on 4G, turn off WiFi, retry with retransmission and very high Avg round trip
- iPhone14-16， Turn on 4G and turn off WiFi. All the above indicators are acceptable
App
- Unity3d project
- .netframe4.0
- C# Socket
Other
Many developers in Chinese forums have provided feedback on this issue
Many developers in Chinese forums have provided feedback on this issue
Generally? Or to Apple?
If anyone has filed a bug about this, I’d appreciate it if you posted the bug number here.
Frankly, this looks like something that needs to be investigated by Apple’s network engineering teams. For that to happen, someone needs to file a bug about it. Ideally, that bug would include:
- A small test project that demonstrates the issue. It’d be best if you wrote this using Xcode and Apple’s APIs, rather third-party tooling, because that rules out the third-party tooling as a source of this issue.
- A sysdiagnose log taken shortly after reproducing the problem.
- On a device with Network Diagnostics debug profile installed. Get that from our Bug Reporting > Profiles and Logs page.
- An RVI packet traces showing the working case on iPhone 16 and the failing case on iPhone 17.
However, this is the ideal situation. If you’re not able to provide all of that info, a bug report with just a sysdiagnose log would still be helpful.
If you do file a bug, please post your bug number, just for the record.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"