Improve spinlock performance for HP-UX, ia64, non-gcc. At least on this architecture, it's very important to spin on a non-atomic instruction and only retry the atomic once it appears that it will succeed. To fix this, split TAS() into two macros: TAS(), for trying to grab the lock the first time, and TAS_SPIN(), for spinning until we get it. TAS_SPIN() defaults to same as TAS(), but we can override it when we know there's a better way.
It's likely that some of the other cases in s_lock.h require similar treatment, but this is the only one we've got conclusive evidence for at present. Branch ------ master Details ------- http://git.postgresql.org/pg/commitdiff/c01c25fbe525869fa81237954727e1eb4b7d4a14 Modified Files -------------- src/backend/storage/lmgr/s_lock.c | 2 +- src/include/storage/s_lock.h | 35 ++++++++++++++++++++++++----------- 2 files changed, 25 insertions(+), 12 deletions(-) -- Sent via pgsql-committers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
