Clarify some comments in vacuumlazy.c

Author: Justin Pryzby
Discussion: https://postgr.es/m/20200113004542.GA26045@telsasoft.com

diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c
index 90caf07427e9c1094091f0aeeca8dae24c738736..8ce501151e913a27ab4be89c4ea1a2d68a714e5b 100644 (file)
--- a/src/backend/access/heap/vacuumlazy.c
+++ b/src/backend/access/heap/vacuumlazy.c
@@ -1507,8 +1507,8 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
                        /*
                         * It should never be the case that the visibility map page is set
                         * while the page-level bit is clear, but the reverse is allowed
-                        * (if checksums are not enabled).  Regardless, set the both bits
-                        * so that we get back in sync.
+                        * (if checksums are not enabled).  Regardless, set both bits so
+                        * that we get back in sync.
                         *
                         * NB: If the heap page is all-visible but the VM bit is not set,
                         * we don't need to dirty the heap page.  However, if checksums
@@ -1563,9 +1563,9 @@ lazy_scan_heap(Relation onerel, VacuumParams *params, LVRelStats *vacrelstats,
                }
 
                /*
-                * If the all-visible page is turned out to be all-frozen but not
-                * marked, we should so mark it.  Note that all_frozen is only valid
-                * if all_visible is true, so we must check both.
+                * If the all-visible page is all-frozen but not marked as such yet,
+                * mark it as all-frozen.  Note that all_frozen is only valid if
+                * all_visible is true, so we must check both.
                 */
                else if (all_visible_according_to_vm && all_visible && all_frozen &&
                                 !VM_ALL_FROZEN(onerel, blkno, &vmbuffer))