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 d5087ef848b..2c11ca40dfc 100644 --- a/src/backend/commands/async.c +++ b/src/backend/commands/async.c @@ -404,6 +404,9 @@ 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) @@ -1234,8 +1237,8 @@ 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 |