Re: non-bulk inserts and tuple routing

On 2018/01/20 7:07, Robert Haas wrote:
> On Fri, Jan 19, 2018 at 3:56 AM, Amit Langote
> <Langote_Amit_f8@lab.ntt.co.jp> wrote:
>> I rebased the patches, since they started conflicting with a recently
>> committed patch [1].
> 
> I think that my latest commit has managed to break this pretty thoroughly.

I rebased it.  Here are the performance numbers again.

* Uses following hash-partitioned table:

create table t1 (a int, b int) partition by hash (a);
create table t1_x partition of t1 for values with (modulus M, remainder R)
...


* Non-bulk insert uses the following code (insert 100,000 rows one-by-one):

do $$
begin
  for i in 1..100000 loop
    insert into t1 values (i, i+1);
  end loop;
end; $$;

Times in milliseconds:

#parts           HEAD        Patched
     8       6148.313       4938.775
    16       8882.420       6203.911
    32      14251.072       8595.068
    64      24465.691      13718.161
   128      45099.435      23898.026
   256      87307.332      44428.126

* Bulk-inserting 100,000 rows using COPY:

copy t1 from '/tmp/t1.csv' csv;

Times in milliseconds:

#parts           HEAD        Patched

     8        466.170        446.865
    16        445.341        444.990
    32        443.544        487.713
    64        460.579        435.412
   128        469.953        422.403
   256        463.592        431.118

Thanks,
Amit