PX Deq Credit: need buffer
This is an idle event. The process is waiting for a message during a parallel execute.
Detailed Description​
The slaves and the QC use table queues for the communication. Each table queue uses buffer to send data between two slaves or a slave and the QC. At a given point in time, only a process can send data, and this is controlled by setting the credit bit on the table queue. A process needs the credit bit if it has to send data via a table queue. The credit bit is sent via a buffer from slave to slave or from a slave to the QC. This wait event indicates that the process is waiting for a buffer from the other slave/QC that sends the credit bit and so that it could send a block.
How to reduce this wait​
Refer to My Oracle Support for the "Master Note for Parallel Execution Wait Events".
Additional Links​
Search online​
If this article doesn't have the information you need you can try searching online. Remember, you can contribute suggestions to this page.