Identifying the Lead Blocker in a Chain

Find a process that is blocking several other processes.

1. In the Perspective Resources view, select the server to monitor, click the drop-down arrow, and select Monitor.
2. In the left pane, select Processes.
3. Click Blocked Processes.
   You see a table with information about blocked and blocking processes, including the lock requests on the basis of which processes are blocked.
4. (Optional for cluster configurations) Click Select User Processes by. Choose All Instances to depict information for the entire cluster, or select a specific instance to see information for only the selected instance of the cluster.
5. The table on the Blocked Processes tab has an entry for each lead blocker; click the arrow to expand the entry and show all the blocked processes in the chain.
   Note: Identifying the lock held by a blocking process is not always straightforward. For example, the blocking process does not necessarily hold a page lock; it might hold a table lock. For this reason, the lock request process that is blocking another process is shown, not the blocking lock.
6. Select a process to populate the tabs at the bottom of the screen with information about that process.
7. Click the tabs to see:

   Option	Description
   Details	Details about the selected process, including the initiating program, transaction information, and network statistics
   SQL	The SQL statement and query plan for the selected process
   Wait Events	Information about wait events for the selected process, including number of waits, wait times, and wait descriptions

8. (Optional) Click the All Processes tab at the top of the window.
   In the table below the bar graph, rows that are highlighted in yellow indicate blocking processes. Rows that are highlighted in red indicate blocked processes.