delay_execution.c File Reference

#include "postgres.h"
#include <limits.h>
#include "optimizer/planner.h"
#include "utils/builtins.h"
#include "utils/guc.h"
#include "utils/inval.h"

Include dependency graph for delay_execution.c:

Go to the source code of this file.

Functions
static PlannedStmt *	delay_execution_planner (Query *parse, const char *query_string, int cursorOptions, ParamListInfo boundParams)
void	_PG_init (void)

Variables
	PG_MODULE_MAGIC
static int	post_planning_lock_id = 0
static planner_hook_type	prev_planner_hook = NULL

Function Documentation

_PG_init()

void _PG_init

(

void

)

Definition at line 75 of file delay_execution.c.

{
    /* Set up the GUC to control which lock is used */
    DefineCustomIntVariable("delay_execution.post_planning_lock_id",
                            "Sets the advisory lock ID to be locked/unlocked after planning.",
                            "Zero disables the delay.",
                            &post_planning_lock_id,
                            0,
                            0, INT_MAX,
                            PGC_USERSET,
                            0,
                            NULL,
                            NULL,
                            NULL);
 
    MarkGUCPrefixReserved("delay_execution");
 
    /* Install our hook */
    prev_planner_hook = planner_hook;
    planner_hook = delay_execution_planner;
}

References DefineCustomIntVariable(), delay_execution_planner(), MarkGUCPrefixReserved(), PGC_USERSET, planner_hook, post_planning_lock_id, and prev_planner_hook.

delay_execution_planner()

static PlannedStmt* delay_execution_planner ( Query *  parse, const char *  query_string, int  cursorOptions, ParamListInfo  boundParams  )

static

Definition at line 42 of file delay_execution.c.

{
    PlannedStmt *result;
 
    /* Invoke the planner, possibly via a previous hook user */
    if (prev_planner_hook)
        result = prev_planner_hook(parse, query_string, cursorOptions,
                                   boundParams);
    else
        result = standard_planner(parse, query_string, cursorOptions,
                                  boundParams);
 
    /* If enabled, delay by taking and releasing the specified lock */
    if (post_planning_lock_id != 0)
    {
        DirectFunctionCall1(pg_advisory_lock_int8,
                            Int64GetDatum((int64) post_planning_lock_id));
        DirectFunctionCall1(pg_advisory_unlock_int8,
                            Int64GetDatum((int64) post_planning_lock_id));
 
        /*
         * Ensure that we notice any pending invalidations, since the advisory
         * lock functions don't do this.
         */
        AcceptInvalidationMessages();
    }
 
    return result;
}

References AcceptInvalidationMessages(), DirectFunctionCall1, Int64GetDatum(), parse(), pg_advisory_lock_int8(), pg_advisory_unlock_int8(), post_planning_lock_id, prev_planner_hook, and standard_planner().

Referenced by _PG_init().

Variable Documentation

PG_MODULE_MAGIC

PG_MODULE_MAGIC

Definition at line 31 of file delay_execution.c.

post_planning_lock_id

int post_planning_lock_id = 0

static

Definition at line 34 of file delay_execution.c.

Referenced by _PG_init(), and delay_execution_planner().

prev_planner_hook

planner_hook_type prev_planner_hook = NULL

static

Definition at line 37 of file delay_execution.c.

Referenced by _PG_init(), and delay_execution_planner().