Re: Parallel Seq Scan

On 20 January 2015 at 14:29, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:

> On Thu, Jan 15, 2015 at 6:57 PM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>
> wrote:
> > On Mon, Jan 12, 2015 at 3:25 AM, Robert Haas <robertmhaas(at)gmail(dot)com>
> wrote:
> > >
> > > Yeah, you need two separate global variables pointing to shm_mq
> > > objects, one of which gets used by pqmq.c for errors and the other of
> > > which gets used by printtup.c for tuples.
> > >
> >
> > Okay, I will try to change the way as suggested without doing
> > switching, but this way we need to do it separately for 'T', 'D', and
> > 'C' messages.
> >
>
> I have taken care of integrating the parallel sequence scan with the
> latest patch posted (parallel-mode-v1.patch) by Robert at below
> location:
>
> http://www.postgresql.org/message-id/CA+TgmoZdUK4K3XHBxc9vM-82khourEZdvQWTfgLhWsd2R2aAGQ@mail.gmail.com
>
> Changes in this version
> -----------------------------------------------
> 1. As mentioned previously, I have exposed one parameter
> ParallelWorkerNumber as used in parallel-mode patch.
> 2. Enabled tuple queue to be used for passing tuples from
> worker backend to master backend along with error queue
> as per suggestion by Robert in the mail above.
> 3. Involved master backend to scan the heap directly when
> tuples are not available in any shared memory tuple queue.
> 4. Introduced 3 new parameters (cpu_tuple_comm_cost,
> parallel_setup_cost, parallel_startup_cost) for deciding the cost
> of parallel plan. Currently, I have kept the default values for
> parallel_setup_cost and parallel_startup_cost as 0.0, as those
> require some experiments.
> 5. Fixed some issues (related to memory increase as reported
> upthread by Thom Brown and general feature issues found during
> test)
>
> Note - I have yet to handle the new node types introduced at some
> of the places and need to verify prepared queries and some other
> things, however I think it will be good if I can get some feedback
> at current stage.
>

Which commit is this based against? I'm getting errors with the latest
master:

thom(at)swift:~/Development/postgresql$ patch -p1 <
~/Downloads/parallel_seqscan_v4.patch
patching file src/backend/access/Makefile
patching file src/backend/access/common/printtup.c
patching file src/backend/access/shmmq/Makefile
patching file src/backend/access/shmmq/shmmqam.c
patching file src/backend/commands/explain.c
Hunk #1 succeeded at 721 (offset 8 lines).
Hunk #2 succeeded at 918 (offset 8 lines).
Hunk #3 succeeded at 1070 (offset 8 lines).
Hunk #4 succeeded at 1337 (offset 8 lines).
Hunk #5 succeeded at 2239 (offset 83 lines).
patching file src/backend/executor/Makefile
patching file src/backend/executor/execProcnode.c
patching file src/backend/executor/execScan.c
patching file src/backend/executor/execTuples.c
patching file src/backend/executor/nodeParallelSeqscan.c
patching file src/backend/executor/nodeSeqscan.c
patching file src/backend/libpq/pqmq.c
Hunk #1 succeeded at 23 with fuzz 2 (offset -3 lines).
Hunk #2 FAILED at 63.
Hunk #3 succeeded at 132 (offset -31 lines).
1 out of 3 hunks FAILED -- saving rejects to file
src/backend/libpq/pqmq.c.rej
patching file src/backend/optimizer/path/Makefile
patching file src/backend/optimizer/path/allpaths.c
patching file src/backend/optimizer/path/costsize.c
patching file src/backend/optimizer/path/parallelpath.c
patching file src/backend/optimizer/plan/createplan.c
patching file src/backend/optimizer/plan/planner.c
patching file src/backend/optimizer/plan/setrefs.c
patching file src/backend/optimizer/util/pathnode.c
patching file src/backend/postmaster/Makefile
patching file src/backend/postmaster/backendworker.c
patching file src/backend/postmaster/postmaster.c
patching file src/backend/tcop/dest.c
patching file src/backend/tcop/postgres.c
Hunk #1 succeeded at 54 (offset -1 lines).
Hunk #2 succeeded at 1132 (offset -1 lines).
patching file src/backend/utils/misc/guc.c
patching file src/backend/utils/misc/postgresql.conf.sample
can't find file to patch at input line 2105
Perhaps you used the wrong -p or --strip option?
The text leading up to this was:
--------------------------
|diff --git a/src/include/access/parallel.h b/src/include/access/parallel.h
|index 761ba1f..00ad468 100644
|--- a/src/include/access/parallel.h
|+++ b/src/include/access/parallel.h
--------------------------
File to patch:

--
Thom