MIME-Version: 1.0
References: 
 <CAEudQApbWon+3Eb9x4WW_D-JkSt2mvfx99dXu9VZ4AeCuTh=fw@mail.gmail.com>
 <CAEudQApEfvhNT1fEPURzVcQH7G0A1ukh_ugoCGaErV6_dbndCQ@mail.gmail.com>
 <CAF+pBj_RS2KErTqQ6ORXjhVzmukG7Ve0wHU1Kq56xjJfFKwVqA@mail.gmail.com>
 <CAEudQAptRymgvmd5hQb2mk-Ft89XcSo_xvC74kv4JBA9v=D4Sg@mail.gmail.com>
 <CAF+pBj-K2bgNQRc9ih01WFmAWUaQtVbS37jLtYdYh5LOwOkF6A@mail.gmail.com>
 <CAF+pBj9M8rCoS-EEBwLiA6hdxm_UNjxMXG9Vc4RU8xifqnQB-g@mail.gmail.com>
 <CAEvyyTjLYVuy0V6gXE9_HgyB4gUftuTZm65gdbacE_OOKk1cqw@mail.gmail.com>
 <CAEudQAoF2xfpA7tgW3gusg0dyMTwTDDwAzBqR_bbv08NBkqv-A@mail.gmail.com>
In-Reply-To: 
 <CAEudQAoF2xfpA7tgW3gusg0dyMTwTDDwAzBqR_bbv08NBkqv-A@mail.gmail.com>
From: lakshmi <lakshmigcdac@gmail.com>
Date: Mon, 23 Mar 2026 10:15:59 +0530
Message-ID: 
 <CAEvyyTjT70OVN_NCcHQ+PodVM7bkPccKPzJcAv0u+eW=qpZDMg@mail.gmail.com>
Subject: Re: Avoid multiple calls to memcpy (src/backend/access/index/genam.c)
To: Ranier Vilela <ranier.vf@gmail.com>
Cc: Bryan Green <dbryan.green@gmail.com>,
 Pg Hackers <pgsql-hackers@postgresql.org>
Content-Type: multipart/alternative; boundary="0000000000007babb7064da9a9c1"
Archived-At: 
 <https://www.postgresql.org/message-id/CAEvyyTjT70OVN_NCcHQ%2BPodVM7bkPccKPzJcAv0u%2BeW%3DqpZDMg%40mail.gmail.com>
Precedence: bulk

--0000000000007babb7064da9a9c1
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

Hi,

Thanks for the reply.

Here are the details of my test setup.

I ran the tests on Debian Linux (6.1.0-10-amd64, x86_64) on an AMD Ryzen 5
7535U (6 cores / 12 threads).

The PostgreSQL version was 19devel, built from source using gcc 12.2.0 with
enable-debug.

For benchmarking, I used pgbench with the following command:
pgbench -p 55432 -d postgres -c 10 -j 4 -T 60

The database was initialized with scale factor 1 (pgbench -i). I ran
multiple iterations for both the original and patched versions and compared
TPS and latency across runs.

All tests were done on the same system under similar conditions.

Please let me know if you=E2=80=99d like me to try any other scenarios or p=
rovide
more details.

Regards,
Lakshmi G

On Fri, Mar 20, 2026 at 4:28=E2=80=AFPM Ranier Vilela <ranier.vf@gmail.com>=
 wrote:

> Hi.
>
> Em sex., 20 de mar. de 2026 =C3=A0s 06:50, lakshmi <lakshmigcdac@gmail.co=
m>
> escreveu:
>
>> Hi,
>>
>> I tried this change on PostgreSQL (19devel) and ran a few simple tests
>> using pgbench to see how it behaves in practice.
>>
>> I used 10 clients and 4 threads and ran each test for 60 seconds.
>>
>> From my runs, the original version was giving around ~663 TPS with ~15.0=
7
>> ms latency.
>> With the patched version, I observed TPS in the range of ~638=E2=80=9365=
7,
>> averaging around ~648 TPS, with latency slightly higher (~15.2=E2=80=931=
5.6 ms).
>>
> Thanks for the benchmark.
> Could you share the tests and the environment?
> compiler
> OS
> etc.
>
> best regards,
> Ranier Vilela
>

--0000000000007babb7064da9a9c1
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr">Hi,<br><br>Thanks for the reply.<br><br>Here are the detai=
ls of my test setup.<br><br>I ran the tests on Debian Linux (6.1.0-10-amd64=
, x86_64) on an AMD Ryzen 5 7535U (6 cores / 12 threads).<br><br>The Postgr=
eSQL version was 19devel, built from source using gcc 12.2.0 with enable-de=
bug.<br><br>For benchmarking, I used pgbench with the following command:<br=
>pgbench -p 55432 -d postgres -c 10 -j 4 -T 60<br><br>The database was init=
ialized with scale factor 1 (pgbench -i). I ran multiple iterations for bot=
h the original and patched versions and compared TPS and latency across run=
s.<br><br>All tests were done on the same system under similar conditions.<=
br><br>Please let me know if you=E2=80=99d like me to try any other scenari=
os or provide more details.<br><br>Regards,<br>Lakshmi G</div><br><div clas=
s=3D"gmail_quote gmail_quote_container"><div dir=3D"ltr" class=3D"gmail_att=
r">On Fri, Mar 20, 2026 at 4:28=E2=80=AFPM Ranier Vilela &lt;<a href=3D"mai=
lto:ranier.vf@gmail.com">ranier.vf@gmail.com</a>&gt; wrote:<br></div><block=
quote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1=
px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"><div>Hi.</div>=
<br><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">Em sex=
., 20 de mar. de 2026 =C3=A0s 06:50, lakshmi &lt;<a href=3D"mailto:lakshmig=
cdac@gmail.com" target=3D"_blank">lakshmigcdac@gmail.com</a>&gt; escreveu:<=
br></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8e=
x;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"=
>Hi,<br><br>I tried this change on PostgreSQL (19devel) and ran a few simpl=
e tests using pgbench to see how it behaves in practice.<br><br>I used 10 c=
lients and 4 threads and ran each test for 60 seconds.<br><br>From my runs,=
 the original version was giving around ~663 TPS with ~15.07 ms latency.<br=
>With the patched version, I observed TPS in the range of ~638=E2=80=93657,=
 averaging around ~648 TPS, with latency slightly higher (~15.2=E2=80=9315.=
6 ms).<br></div></blockquote><div>Thanks for the benchmark.</div><div>Could=
 you share the tests and the environment?</div><div>compiler</div><div>OS</=
div><div>etc.</div><div><br></div><div>best regards,</div><div>Ranier Vilel=
a</div></div></div>
</blockquote></div>

--0000000000007babb7064da9a9c1--