Re: Perf Benchmarking and regression.

Hi Andres,

I am extremely sorry for the delayed response. As suggested by you, I have
taken the performance readings at 128 client counts after making the
following two changes:

*1).* Removed AddWaitEventToSet(FeBeWaitSet, WL_POSTMASTER_DEATH, -1, NULL,
NULL); from pq_init(). Below is the git diff for the same.

diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c
index 8d6eb0b..399d54b 100644
--- a/src/backend/libpq/pqcomm.c
+++ b/src/backend/libpq/pqcomm.c
@@ -206,7 +206,9 @@ pq_init(void)
AddWaitEventToSet(FeBeWaitSet, WL_SOCKET_WRITEABLE,
MyProcPort->sock,
NULL, NULL);
AddWaitEventToSet(FeBeWaitSet, WL_LATCH_SET, -1, MyLatch, NULL);
+#if 0
AddWaitEventToSet(FeBeWaitSet, WL_POSTMASTER_DEATH, -1, NULL, NULL);
+#endif

*2).* Disabled the guc vars "bgwriter_flush_after",
"checkpointer_flush_after" and "backend_flush_after" by setting them to
zero.

After doing the above two changes below are the readings i got for 128
client counts:

*CASE :* Read-Write Tests when data exceeds shared buffers.

Non Default settings and test
./postgres -c shared_buffers=8GB -N 200 -c min_wal_size=15GB -c
max_wal_size=20GB -c checkpoint_timeout=900 -c maintenance_work_mem=1GB -c
checkpoint_completion_target=0.9 &

./pgbench -i -s 1000 postgres

./pgbench -c 128 -j 128 -T 1800 -M prepared postgres

*Run1 :* tps = 9690.678225
*Run2 :* tps = 9904.320645
*Run3 :* tps = 9943.547176

Please let me know if i need to take readings with other client counts as
well.

*Note:* I have taken these readings on postgres master head at,

commit 91fd1df4aad2141859310564b498a3e28055ee28
Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Date: Sun May 8 16:53:55 2016 -0400

With Regards,
Ashutosh Sharma
EnterpriseDB: *http://www.enterprisedb.com <http://www.enterprisedb.com>*

On Wed, May 11, 2016 at 3:53 AM, Andres Freund <andres(at)anarazel(dot)de> wrote:

> Hi,
>
> On 2016-05-06 21:21:11 +0530, Mithun Cy wrote:
> > I will try to run the tests as you have suggested and will report the
> same.
>
> Any news on that front?
>
> Regards,
>
> Andres
>
>
> --
> Sent via pgsql-hackers mailing list (pgsql-hackers(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-hackers
>