diff options
| author | Andres Freund <andres@anarazel.de> | 2018-11-09 20:43:56 -0800 |
|---|---|---|
| committer | Andres Freund <andres@anarazel.de> | 2018-11-09 20:43:56 -0800 |
| commit | 5fde047f2b41e71706d4ea9e8eb0a401f64192c1 (patch) | |
| tree | bdcd9d4d0a56df9ef9fe246c7cb477c8b947073e | |
| parent | 5fc1670bad9bfa138be1c790d529249e0706d38e (diff) | |
Combine two flag tests in GetSnapshotData().
Previously the code checked PROC_IN_LOGICAL_DECODING and
PROC_IN_VACUUM separately. As the relevant variable is marked as
volatile, the compiler cannot combine the two tests. As
GetSnapshotData() is pretty hot in a number of workloads, it's
worthwhile to fix that.
It'd also be a good idea to get rid of the volatiles altogether. But
for one that's a larger patch, and for another, the code after this
change still seems at least as easy to read as before.
Author: Andres Freund
Discussion: https://postgr.es/m/20181005172955.wyjb4fzcdzqtaxjq@alap3.anarazel.de
| -rw-r--r-- | src/backend/storage/ipc/procarray.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index 908f62d37e2..c861f3e17f9 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -1589,14 +1589,11 @@ GetSnapshotData(Snapshot snapshot) TransactionId xid; /* - * Backend is doing logical decoding which manages xmin - * separately, check below. + * Skip over backends doing logical decoding which manages xmin + * separately (check below) and ones running LAZY VACUUM. */ - if (pgxact->vacuumFlags & PROC_IN_LOGICAL_DECODING) - continue; - - /* Ignore procs running LAZY VACUUM */ - if (pgxact->vacuumFlags & PROC_IN_VACUUM) + if (pgxact->vacuumFlags & + (PROC_IN_LOGICAL_DECODING | PROC_IN_VACUUM)) continue; /* Update globalxmin to be the smallest valid xmin */ |