Type: | bool |
Default: | on |
Context: | user |
Restart: | false |
Since: | 11 |
Allows the leader process to execute the query plan under Gather
and Gather Merge
nodes instead of waiting for worker processes. The default is on
. Setting this value to off
reduces the likelihood that workers will become blocked because the leader is not reading tuples fast enough, but requires the leader process to wait for worker processes to start up before the first tuples can be produced. The degree to which the leader can help or hinder performance depends on the plan type, number of workers and query duration.
On StackOverflow
On pgsql-hackers
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- Re: [PATCH] Add extra statistics to explain for Nested Loop