Add vacuum_delay_point call in compute_index_stats's per-sample-row loop.

Slow functions in index expressions might cause this loop to take long
enough to make it worth being cancellable.  Probably it would be enough
to call CHECK_FOR_INTERRUPTS here, but for consistency with other
per-sample-row loops in this file, let's use vacuum_delay_point.

Report and patch by Jeff Janes.  Back-patch to all supported branches.

diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 0e876904d96f033d4915cbdd1d652ddd4fc911d7..53fded1795372dd02132ce8ec06cbeb61e3772bb 100644 (file)
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -693,6 +693,8 @@ compute_index_stats(Relation onerel, double totalrows,
                {
                        HeapTuple       heapTuple = rows[rowno];
 
+                       vacuum_delay_point();
+
                        /*
                         * Reset the per-tuple context each time, to reclaim any cruft
                         * left behind by evaluating the predicate or index expressions.