diff options
author | Peter Geoghegan | 2023-01-24 23:15:33 +0000 |
---|---|---|
committer | Peter Geoghegan | 2023-01-24 23:15:33 +0000 |
commit | 8f8f11593258d04e9a58365865f7daf123e24bb1 (patch) | |
tree | df2ba1b8e9ebf368cb26f058de7566cc8f1b00a4 | |
parent | 1249371632db9d97786edfb3d58c3e89e75b9519 (diff) |
Update more obsolete multixact.c comments.
Update some remaining comments in multixact.c that still described SLRU
truncation as happening in the checkpointer, rather than during VACUUM.
Follow-up to commit 5212d447.
Shi yu, with tweaks by me.
Author: Shi yu <[email protected]>
Discussion: https://postgr.es/m/OSZPR01MB631066BF246F8F74E83222FCFDC69@OSZPR01MB6310.jpnprd01.prod.outlook.com
-rw-r--r-- | src/backend/access/transam/multixact.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c index e75e1fdf74..fe6698d5ff 100644 --- a/src/backend/access/transam/multixact.c +++ b/src/backend/access/transam/multixact.c @@ -261,7 +261,7 @@ typedef struct MultiXactStateData * we compute it (using nextMXact if none are valid). Each backend is * required not to attempt to access any SLRU data for MultiXactIds older * than its own OldestVisibleMXactId[] setting; this is necessary because - * the checkpointer could truncate away such data at any instant. + * the relevant SLRU data can be concurrently truncated away. * * The oldest valid value among all of the OldestMemberMXactId[] and * OldestVisibleMXactId[] entries is considered by vacuum as the earliest @@ -669,8 +669,8 @@ MultiXactIdSetOldestMember(void) * * We set the OldestVisibleMXactId for a given transaction the first time * it's going to inspect any MultiXactId. Once we have set this, we are - * guaranteed that the checkpointer won't truncate off SLRU data for - * MultiXactIds at or after our OldestVisibleMXactId. + * guaranteed that SLRU data for MultiXactIds >= our own OldestVisibleMXactId + * won't be truncated away. * * The value to set is the oldest of nextMXact and all the valid per-backend * OldestMemberMXactId[] entries. Because of the locking we do, we can be |