On Wed, Jan 25, 2012 at 5:16 PM, Merlin Moncure <mmoncure@xxxxxxxxx> wrote: > On Wed, Jan 25, 2012 at 7:43 AM, Claudio Freire <klaussfreire@xxxxxxxxx> wrote: >> I know squat about how to implement this, but I've been considering >> picking the low hanging fruit on that tree and patching up PG to try >> the concept. Many of the items above would require a thread-safe >> execution engine, which may be quite hard to get and have a >> significant performance hit. Some don't, like parallel sort. > > This was just discussed on -hackers yesterday -- see thread > 'multithreaded query planner'. In short, judging by the comments of > some of the smartest people working on this project, it sounds like > using threads to attack this is not going to happen, ever. Note you > can probably still get parallel execution in other ways, using > processes, shared memory, etc, so I'd consider researching in that > direction. If you mean this[0] thread, it doesn't show anything conclusive against, say, parallel sort or pipelining. But I agree, checking the code, it would be really tough to get any more than parallel sorting by primitive types with threads. Processes, however, show promise. [0] http://archives.postgresql.org/pgsql-hackers/2012-01/msg00734.php -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
