Re: Speed up transaction completion faster after many relations areaccessed in a transaction

On 2019/04/05 5:42, Peter Eisentraut wrote:
> On 2019-04-04 06:58, Amit Langote wrote:
>> Also, since the "speed up partition planning" patch went in (428b260f8),
>> it might be possible to see the performance boost even with the
>> partitioning example you cited upthread.
> 
> I can't detect any performance improvement with the patch applied to
> current master, using the test case from Yoshikazu Imai (2019-03-19).

I was able to detect it as follows.

* partitioned table setup:

$ cat ht.sql
drop table ht cascade;
create table ht (a int primary key, b int, c int) partition by hash (a);
select 'create table ht' || x::text || ' partition of ht for values with
(modulus 8192, remainder ' || (x)::text || ');' from generate_series(0,
8191) x;
\gexec

* pgbench script:

$ cat select.sql
\set param random(1, 8192)
select * from ht where a = :param

* pgbench (5 minute run with -M prepared)

pgbench -n -M prepared -T 300 -f select.sql

* tps:

plan_cache_mode = auto

   HEAD: 1915 tps
Patched: 2394 tps

plan_cache_mode = custom (non-problematic: generic plan is never created)

   HEAD: 2402 tps
Patched: 2393 tps

Thanks,
Amit