"failed to acquire resources on one or more segments" Displayed When Greenplum Is Running SQL Statements

Symptom

Before KAEzip is enabled, the message "failed to acquire resources on one or more segments" is displayed when Greenplum is running SQL statements.

Key Process and Cause Analysis

The max_connections parameter is set to a small value, as a result, segment data fails to be obtained or data obtaining times out.

Conclusion and Solution

Increase the value of max_connections, that is, the maximum number of Greenplum connections. At the same time, the value of max_prepared_transactions must be the same as that of max_connections on the master node:

gpconfig -c max_connections -v 2500 -m 500
gpconfig -c max_prepared_transactions -v 500