Re: A reloption for partitioned tables - parallel_workers

Hi,

On Tue, Feb 23, 2021 at 3:12 PM houzj(dot)fnst(at)fujitsu(dot)com
<houzj(dot)fnst(at)fujitsu(dot)com> wrote:
> > Here is an updated version of the Seamus' patch that takes into account these
> > and other comments received on this thread so far.
> > Maybe warrants adding some tests too but I haven't.
> >
> > Seamus, please register this patch in the next commit-fest:
> > https://commitfest.postgresql.org/32/
> >
> > If you haven't already, you will need to create a community account to use that
> > site.
>
> It seems the patch does not include the code that get the parallel_workers from new struct " PartitionedTableRdOptions ",
> Did I miss something ?

Aren't the following hunks in the v2 patch what you meant?

diff --git a/src/backend/access/common/reloptions.c
b/src/backend/access/common/reloptions.c
index c687d3ee9e..f8443d2361 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -377,7 +377,7 @@ static relopt_int intRelOpts[] =
{
"parallel_workers",
"Number of parallel processes that can be used per executor node for
this relation.",
- RELOPT_KIND_HEAP,
+ RELOPT_KIND_HEAP | RELOPT_KIND_PARTITIONED,
ShareUpdateExclusiveLock
},
-1, 0, 1024
@@ -1962,12 +1962,18 @@ bytea *
partitioned_table_reloptions(Datum reloptions, bool validate)
{
/*
- * There are no options for partitioned tables yet, but this is able to do
- * some validation.
+ * Currently the only setting known to be useful for partitioned tables
+ * is parallel_workers.
*/
+ static const relopt_parse_elt tab[] = {
+ {"parallel_workers", RELOPT_TYPE_INT,
+ offsetof(PartitionedTableRdOptions, parallel_workers)},
+ };
+
return (bytea *) build_reloptions(reloptions, validate,
RELOPT_KIND_PARTITIONED,
- 0, NULL, 0);
+ sizeof(PartitionedTableRdOptions),
+ tab, lengthof(tab));
}

/*

diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index 10b63982c0..fe114e0856 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -308,6 +308,16 @@ typedef struct StdRdOptions
bool vacuum_truncate; /* enables vacuum to truncate a relation */
} StdRdOptions;

+/*
+ * PartitionedTableRdOptions
+ * Contents of rd_options for partitioned tables
+ */
+typedef struct PartitionedTableRdOptions
+{
+ int32 vl_len_; /* varlena header (do not touch directly!) */
+ int parallel_workers; /* max number of parallel workers */
+} PartitionedTableRdOptions;
+
#define HEAP_MIN_FILLFACTOR 10
#define HEAP_DEFAULT_FILLFACTOR 100

--
Amit Langote
EDB: http://www.enterprisedb.com