I could see that affinity between threads and cores and did wonder whether it breaking at 8 threads was somewhat coincidental to having 4 cores.
As I cannot know in advance which of the days in the logs will be most demanding, I have no choice but to iterate in the safest possible way.
I did a test to go through each day at a time and for each day, create 4 tasks to process 6 hours each. Once they are complete, I create the next 4 for the next day and so on until it completes. It works on this device but has no benefit. The overhead of all the task management seemed to outweigh a single threaded loop just churning its way through the sequence.
So for now, I'm going to assume that the safety compromise and complexity of a fancy approach to speeding this up is not going to be worth it. It's an optimisation for the future but given your answer, I'm happy I'm not doing anything wrong and just need to live with the tradeoff which gives the safest result on all possible deployment targets.
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It looks like iOS always wants to validate the server trust for EAP-PEAP/EAP-TTLS (TLS is a given).Use a mobileconfig with the server certificate embedded. Your wildcard certificate will be fine. It can all be done through Apple Configurator.I notice that the docs say you should just be able to setup a list of trusted domains in the mobileconfig and that could be an alternative to embedding the certificate, but that doesn't seem to work. Could be a bug?iOS11 NEHotspotConfiguration APIs seem not to attach the certificate properly as well so that route may not be working. Another bug maybe?
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I should say that I forgot to include in the code excerpts above that in both the getquery and setquery I have added the key pair(id)kSecAttrAccessGroupid)@"ABCDEE12345.com.apple.networkextensionsharing",Where the prefix is the team id. This is similar but not exactly as per the documentation which asks for the following (note there is no dot between the prefix and com $(TeamIdentifierPrefix)com.apple.networkextensionsharing(so this might be an error in the documentation.I can see the certificates in the keychain when debugging in xcode so it looks fine but the console gives out these errors.error 12:40:10.466294 +0100 nehelper -[NEHotspotConfiguration valid:587 NEHotspotConfiguration failed to find the certificate item in the keychain.error 12:40:10.467728 +0100 nehelper -[NEHotspotConfiguration valid:653 NEHotspotConfiguration invalid trusted server certificate referenceserror 12:40:10.468039 +0100 nehelper -[NEHotspotConfiguration valid:743 NEHotspotConfiguration invalid EAP settings.error 12:40:10.468380 +0100 nehelper -[NEHelperHotspotConfiguration:461 NEHelperHotspotConfigurationManager failed to validate the configuration data for add/update request.In summary, the getquery and SecItemCopyMatching work well in the code. But the NEHelper is not able to access the certificate and I'm unsure why?
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New bug filed which might offer some insight into the above issues.Wi-Fi system got stuck in a scan and never auto-joined. Had to restart the device. Might shed some light into the system bugs discussed herebug: 34790698If there is any other specific testing this community can do on Wi-Fi please tell us. The issues with Wi-Fi in iOS 11 and Hotspot Helper are causing issues to those of us on the hook for supporting apps which use this.
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Thanks for the update. I also have this as an outstanding bug report (duped to the one you mention).I also think it is a bug that when an annotated network gets connected, the annotation is usually lost. I have this as bug 33288110 which does not seem to have been acknowledged. Can you confirm if this is the expected behaviour or a bug (I guess related to the one above).
