> WaitLatch function the same variable worker_spi_naptime without referencing > the configuration created in _PG_init. Am I missing something here?
You can see the declaration of that variable up on line 56. It's just an int variable static to worker_spi.c.
The code you saw in _PG_init registers that variable to the Grand Unified Configuration system (you can see where the address of the variable, &worker_spi_naptime, is passed in that registration), so the GUC system can handle setting or querying the value from SQL (and config files, etc.).
You can read more about the GUC system in src/backend/utils/misc/README, src/backend/utils/misc/guc.c, and src/include/utils/guc.h.
-Chap
Thank you. I did see worker_spi_naptime definition, but I wanted to pass worker_spi_naptime as an argument instead into worker_spi_main so that I can control via SQL interface how frequently the worker SQL executes. Is this possible?