On Thu, Aug 21, 2014 at 2:47 AM, Haribabu Kommi <kommi.harib...@gmail.com> wrote: > Implementation of "Parallel Sequence Scan" > > Approach: > > 1."Parallel Sequence Scan" can achieved by using the background > workers doing the job of actual sequence scan including the > qualification check also. > > 2. Planner generates the parallel scan plan by checking the possible > criteria of the table to do a parallel scan and generates the tasks > (range of blocks). > > 3. In the executor Init phase, Try to copy the necessary data required > by the workers and start the workers. > > 4. In the executor run phase, just get the tuples which are sent by > the workers and process them further in the plan node execution.
Well, this is something I've thought quite a bit about already. Many of my thoughts on parallelism are here: https://wiki.postgresql.org/wiki/Parallel_Sort Although the page title is parallel sort, many of the concerns are applicable to parallelism of any sort. I posted some patches containing some of the necessary infrastructure here: http://archives.postgresql.org/message-id/CA+Tgmoam66dTzCP8N2cRcS6S6dBMFX+JMba+mDf68H=kakn...@mail.gmail.com I seem to have forgotten to add that message to the CommitFest. Crap. -- 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
