Python App Engine: Task Queues
I've solved this in the past by keeping the status for the tasks in memcached, and polling (via Ajax) to determine when the tasks are finished.  
If you go this way, it's best if you can always "manually" determine the status of the tasks without looking in memcached, since there's always the (slim) chance that memcache will go down or will get cleared or something as a task is running.
I need to import some data to show it for user but page execution time exceeds 30 second limit. So I decided to split my big code into several tasks and try Task Queues. I add about 10-20 tasks to queue and app engine executes tasks in parallel while user is waiting for data. How can I determine that my tasks are completed to show user data ASAP? Can I somehow iterate over active tasks?