Various micro-optimizations for GetSnapshopData(). Heikki Linnakangas had the idea of rearranging GetSnapshotData to avoid checking for sub-XIDs when no top-level XID is present. This patch does that plus further a bit of further, related rearrangement. Benchmarking show a significant improvement on unlogged tables at higher concurrency levels, and mostly indifferent result on permanent tables (which are presumably bottlenecked elsewhere). Most of the benefit seems to come from using the new NormalTransactionIdPrecedes() macro rather than the function call TransactionIdPrecedes().
Branch ------ master Details ------- http://git.postgresql.org/pg/commitdiff/0d76b60db4684d3487223b003833828fe9655fe2 Modified Files -------------- src/backend/storage/ipc/procarray.c | 37 ++++++++++++++++++---------------- src/include/access/transam.h | 4 +++ 2 files changed, 24 insertions(+), 17 deletions(-) -- Sent via pgsql-committers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
