Too many devices try to get /apple-app-site-association file at once

Number:rdar://19215256 Date Originated:11-Dec-2014 01:38 PM
Status:Open Resolved:
Product:iOS Product Version:8+
Classification:Other Bug Reproducible:Always
We released a few days ago a new version of our main app, the main feature being Handoff support.
The night after the release, our web server got around many requests at once at midnight, all requests being for /apple-app-site-association. All those requests had a user agent of swcd, for exampe:
swcd (unknown version) CFNetwork/711.1.16 Darwin/14.0

Steps to Reproduce:
Release a new version of an iOS app with Handoff support.

Expected Results:
Even if all the devices must get the last version of that file, make sure they don't all try to get it at the same time. For example add a random wait before downloading to not overload the servers.

Actual Results:
All the iOS devices with automatic update turned on try to download the same file at midnight.

iOS 8+

Also we have mentioned to this problem to technical support team.

iOS devices with Handoff support.


The release of iOS 9.3 appears to have resolved this issue for us:

We're seeing this issue as well. The spikes in the graph below are all requests for the /apple-app-site-association file. It would be courteous to add a splay time to this scheduled task.

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