Re: New Table Access Methods for Multi and Single Inserts

On Sat, Feb 20, 2021 at 11:15 AM Bharath Rupireddy
<bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote:

> > Please review the v3 patch set further.
>
> Below is the performance gain measured for CREATE TABLE AS with the
> new multi insert am propsed in this thread:
>
> case 1 - 2 integer(of 4 bytes each) columns, 3 varchar(8), tuple size
> 59 bytes, 100mn tuples
> on master - 185sec
> on master with multi inserts - 121sec, gain - 1.52X
>
> case 2 - 2 bigint(of 8 bytes each) columns, 3 name(of 64 bytes each)
> columns, 1 varchar(8), tuple size 241 bytes, 100mn tuples
> on master - 367sec
> on master with multi inserts - 291sec, gain - 1.26X
>
> case 3 - 2 integer(of 4 bytes each) columns, tuple size 32 bytes, 100mn tuples
> on master - 130sec
> on master with multi inserts - 105sec, gain - 1.23X
>
> case 4 - 2 bigint(of 8 bytes each) columns, 16 name(of 64 bytes each)
> columns, tuple size 1064 bytes, 10mn tuples
> on master - 120sec
> on master with multi inserts - 115sec, gain - 1.04X

Performance numbers look good, especially with the smaller tuple size.
I was looking into the patch and I have a question.

+static inline void
+table_insert_v2(TableInsertState *state, TupleTableSlot *slot)
+{
+ state->rel->rd_tableam->tuple_insert_v2(state, slot);
+}
+
+static inline void
+table_multi_insert_v2(TableInsertState *state, TupleTableSlot *slot)
+{
+ state->rel->rd_tableam->multi_insert_v2(state, slot);
+}

Why do we need to invent a new version table_insert_v2? And also why
it is named table_insert* instead of table_tuple_insert*?

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com