Postgres Pro allows you to bulk insert data into the same table in multiple threads simultaneously, bypassing the Postgres Pro buffer manager. This feature is designed for the following scenarios:

Using multi-segment insertion requires no special preparation or custom parameters when connecting a new client. Any client backend process can start inserting data in multi-segment mode.

Before writing data to a table, specify the name of the table in the multi_segment_relname parameter. You can set this parameter multiple times in a session so that a single client backend can perform multi-segment insertion into several tables, switching between its dedicated table segments.

To avoid lock conflicts, each backend creates a dedicated table segment for inserting data. The backends that are not performing multi-segment insertion cannot access this segment and the corresponding table, even for reading. The backends that are currently using the multi-segment mechanism can read data from the dedicated table segments that do not belong to them, but they can write data only to their own segments. When a segment is full, the backend immediately creates another segment and continues writing data to the new segment.

Before performing the first INSERT, a backend acquires a session-level exclusive lock on the table specified in the multi_segment_relname parameter. This lock blocks access to the table for all processes, including autovacuum, except the backends that perform multi-segment insertion to this table. No operations other than multi-segment insertion are available.

Data pages that have been inserted via the multi-segment mechanism act like regular Postgres Pro data pages: they are synced to disk during the COMMIT or CHECKPOINT operations for a higher level of safety.