On Thu, Dec 13, 2012 at 3:03 PM, Andres Freund <and...@2ndquadrant.com> wrote: > It moves a computation of the sort of: > > result -= vacuum_defer_cleanup_age; > if (!TransactionIdIsNormal(result)) > result = FirstNormalTransactionId; > > inside ProcArrayLock. But I can't really imagine that to be relevant...
I can. Go look at some of the 9.2 optimizations around GetSnapshotData(). Those made a BIG difference under heavy concurrency and they were definitely micro-optimization. For example, the introduction of NormalTransactionIdPrecedes() was shockingly effective. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers