nw_host_stats_add_src recv too small, received 24, expected 28 nw_host_stats_add_src recv too small, received 24, expected 28 swift swift

nw_host_stats_add_src recv too small, received 24, expected 28


This is a bug with logs in Xcode8 + iOS10.


We can get round it in this way:

When on simulator, add the Name OS_ACTIVITY_MODE and the ValueVariables disable and check it (Product -> Scheme -> Edit Scheme -> Run -> Arguments -> Environment).

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When on device, only add OS_ACTIVITY_MODE and check it(don't add the Value). You'll see the NSLog in the Xcode8 Console.

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Cause: iOS 10 & Xcode 8. Also can be replicated by an odd inputField bug:

Issue belongs to an InputField whom width is smaller than the inputs chars : 96px vs (4 * 28px) This leads to a 100% CPU and it is fixed when width is set to 128px

Link to the above fix and reasoning

Or just silence everything:

  • Press ⌘<
  • Edit simulator scheme by adding or setting the OS_ACTIVITY_MODE under Environment Variables in the Run Arguments to a value of disable.
  • Do the same for the device but remove the value for OS_ACTIVITY_MODE , leaving it empty. The logs will display for the device as they should.


I found this answer in a video on Reddit located here: https://www.reddit.com/r/ios/comments/5p0fvy/xcode_nw_host_stats_add_src_recv_too_small/

This warning comes from XCode and can be disabled by adding an Environmental variable to the Scheme's Run section. The Environmental name is OS_ACTIVITY_MODE and the value is "disable".

This appears to suppress all of the "nw_" warning messages. Note that this just suppresses the warnings. I'm not sure if the warnings are significant or not or whether this indicates that there are "real" underlying problems that should be fixed.

How to edit a Scheme's Run Environmental Variables section in XCode

Adding the OS_ACTIVITY_MODE value of "disable"