Event Queue - GameAnalytics/GA-SDK-CPP GitHub Wiki
Whenever an event is added (and validated) it will be added to a local database queue.
Interval
Every 8 seconds the SDK will start a task for submitting queued events since last submit. This processing is done in a separate low-priority thread that will have minimum impact on performance. The payload is gzipped and will therefore only consume a small amount of bandwidth.
Offline
When a device is offline the events are still added to the queue. When the device is online it will submit.