Ongoing Task Stats: Subscription Stats

• A Subscription Task is an ongoing task in which the server sends documents that match a query defined on the task to a client.

• The server sends the documents in batches in an orderly manner, waiting for the client to acknowledge the consumption of each batch before sending the next.

• Learn more about data subscription tasks here.

• Studio's Ongoing Task Stats view draws a track for each of a database's ongoing tasks.
  This page covers the activity of a data subscription.

• In this article:

  • Subscription Stats Closed View
  • Subscription Stats Expanded View
  • Connection Event Indicators

Subscription Stats

Subscription Stats Closed View

1. Task Type
   Click the arrow or the task type to toggle Closed/Expanded View.
2. Task Name
3. Query
   Click to display the subscription query.
4. Task Bar
   • Hover over the bar to display a tooltip with the task's information.
   • Click the bar for the expanded view.
   • Click and Drag the bar to slide the graph.
   • Zoom in & out using the mouse wheel.

Subscription Stats Expanded View

• Client Connection
  • Duration
    Overall connection time.
  • Client URL
  • Strategy
    The strategy used by the client.
  • Number of batches acknowledged
    The number of batches whose processing was completed & confirmed by the client.
  • Size of all batches
    The total size of all batches sent in this connection.
• Documents Batch
  • Total duration
    The amount of time it took to deliver this batch.
  • Documents sent in batch
    The number of documents delivered in this batch.
  • Documents size
    Overall size of Transferred documents.
  • Included Documents
    Included Counters
    Included Time Series entries
    Number of included documents, counters, and time series
• Sending Documents
  The time it took the server to send the documents in this batch.
• Waiting for ACK
  The time it took the client to acknowledge this batch.

Connection Event Indicators

Connection Event Indicators signify events related to the initiation, state, or termination of a client connection.

• Indicators are shown in both the collapsed and the expanded task tracks.
• Hovering over a connection event indicator displays the details of the event, when details are available.
  Connection Initiated
  
  Connection Aborted
  
  The client has forcibly aborted the connection.
  Connection Rejected
  
  A subscription task handles only a single client/connection at a time.
  A client that uses the OpenIfFree strategy has attempted to open a connection to the subscription task but was rejected because the task is already occupied by another client.
  Pending Connection
  

1. Client A connects to the subscription task.
2. Client B, using the WaitForFree strategy, attempts to connect the task.
   Discovering that the task is occupied, Client B is now pending, waiting for Client A to disconnect.
   The dotted yellow line shows the pending period for Client B.
3. Client A disconnects from the subscription task.
4. Client B starts a new connection to the subscription task.