> The maintenance costs and update contention for such a datastructure > would render this completely impractical, even if consulting it were > free. >
Thanks for the reply. a) Only one transaction would be updating its commit status. Its multiple readers Vs Single Writer for the position of a particular transation( a memory location ). So a reader-writer lock would reduce the contention. Moreover it releases the need for the synchronization that happens with global pg_procs now. For example something like a select which would only query the old data will never access this structure. I am right now not able to think of anything on the maintenance cost perspective. Gokul.
