What do you mean by 'Priority Job Slot'?
Let's get one important thing out of the way first: we will handle any traffic that you send us. However, if you are sending us gigantic amounts of data at once, and expect everything to be processed instantenous as well, then we will need to reserve some capacity. The more data you want to be handled concurrently, the more reserved Priority Job Slot you will require.
If you exceed your number of Priority Job Slot, we will start queueing your subsequent jobs. If your use case demands high traffic with a real-time feel to it, we recommend that you do not leave things to chance and reserve more Priority Job Slots. You can also purchase them as a complementary add-on to your plan instead of having to upgrade your plan. Just reach out to support about this.
What exactly determines how many job slots are being used up? Basically each Encoding Job takes up a varying number of Job Slots which your account has available at a given time. For the full list on how many Job Slots are used up at a given time from each Robot, please see below.
Note that the limit is configurable per Plan, and that it acts per region. So if your Plan had 500 Priority Job Slots available, that would be 500 in each of 3 regions that Transloadit operates in.
To learn more about Queues and what you can do to avoid them, read the Queue section in our API docs.