Обсуждение: pgsql: Replace CAS loop with single TAS in ProcArrayGroupClearXid()

Replace CAS loop with single TAS in ProcArrayGroupClearXid()

Single pg_atomic_exchange_u32() is expected to be faster than loop of
pg_atomic_compare_exchange_u32().  Also, it would be consistent with
clog group update code.

Discussion: https://postgr.es/m/CAPpHfdtxLsC-bqfxFcHswZ91OxXcZVNDBBVfg9tAWU0jvn1tQA%40mail.gmail.com
Reviewed-by: Amit Kapila

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/2f39106a209e647d7b1895331fca115f9bb6ec8d

Modified Files
--------------
src/backend/storage/ipc/procarray.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)