Scott Carey escribió: > Your description (much of which I cut out) is exactly how I understood > it until Simon Riggs' post which changed my view and understanding. > Under that situation, waking all shared will leave all XXXXX at the > front and hence alternate shared/exclusive/shared/exclusive as long as > both types are contending. Simon's post changed my view. Below is > some cut/paste from it:
Simon's explanation, however, is at odds with the code. http://git.postgresql.org/?p=postgresql.git;a=blob;f=src/backend/storage/lmgr/lwlock.c There is "queue jumping" in the regular (heavyweight) lock manager, but that's a pretty different body of code. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
