> On Tue, Sep 22, 2015 at 9:12 PM, Kouhei Kaigai <kai...@ak.jp.nec.com> wrote: > > Oh... I did exactly duplicated job a few days before. > > > https://github.com/kaigai/sepgsql/blob/readfuncs/src/backend/nodes/readfuncs > .c > > Please post the patch here, and clarify that it is under the PostgreSQL > license. > Of course. I intend to submit.
> > Regarding of CustomScan node, I'd like to run on worker process as soon as > > possible once it gets supported. I'm highly motivated. > > Great. > > > Andres raised a related topic a few weeks before: > > > http://www.postgresql.org/message-id/20150825181933.GA19326@awork2.anarazel. > de > > > > Here are two issues: > > > > * How to reproduce "methods" pointer on another process. Extension may not > > be > > loaded via shared_preload_libraries. > > The parallel mode stuff already has code to make sure that the same > libraries that were loaded in the original backend get loaded in the > new one. But that's not going to make the same pointer valid there. > > > -> One solution is to provide a pair of library and symbol name of the > > method > > table, instead of the pointer. I think it is a reasonable idea. > > I agree. > > > * How to treat additional output of TextOutCustomScan. > > -> Here are two solutions. (1) Mark TextOutCustomScan as an obsolete > > callback, > > however, it still makes Andres concern because we need to form/deform > > private > > data for copyObject safe. (2) Add TextReadCustomScan (and > NodeEqualCustomScan?) > > callback to process private fields. > > I don't see how making it obsolete solves anything. Any node that > wants to run in a worker needs to have outfuncs and readfuncs support. > In actually, I'm inclined to the (2) rather than (1). In case of (2), we shall need two new callbacks on _copyCustomScan and _readCustomScan. I'll try to make up. Thanks, -- NEC Business Creation Division / PG-Strom Project KaiGai Kohei <kai...@ak.jp.nec.com> -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
