diff options
Diffstat (limited to 'src/backend/commands/async.c')
| -rw-r--r-- | src/backend/commands/async.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/src/backend/commands/async.c b/src/backend/commands/async.c index 2514ffb6443..d8f1408e9e9 100644 --- a/src/backend/commands/async.c +++ b/src/backend/commands/async.c @@ -403,6 +403,9 @@ static void ClearPendingActionsAndNotifies(void); /* * We will work on the page range of 0..QUEUE_MAX_PAGE. + * + * Since asyncQueueIsFull() blocks creation of a page that could precede any + * extant page, we need not assess entries within a page. */ static bool asyncQueuePagePrecedes(int p, int q) @@ -1233,8 +1236,8 @@ asyncQueueIsFull(void) * logically precedes the current global tail pointer, ie, the head * pointer would wrap around compared to the tail. We cannot create such * a head page for fear of confusing slru.c. For safety we round the tail - * pointer back to a segment boundary (compare the truncation logic in - * asyncQueueAdvanceTail). + * pointer back to a segment boundary (truncation logic in + * asyncQueueAdvanceTail does not do this, so doing it here is optional). * * Note that this test is *not* dependent on how much space there is on * the current head page. This is necessary because asyncQueueAddEntries |