Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1Ydf6B-0004ca-J2 for pgsql-performance@arkaria.postgresql.org; Thu, 02 Apr 2015 13:23:55 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1Ydf6B-0000ts-37 for pgsql-performance@arkaria.postgresql.org; Thu, 02 Apr 2015 13:23:55 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1Ydf6A-0000tm-A1 for pgsql-performance@postgresql.org; Thu, 02 Apr 2015 13:23:54 +0000 Received: from mail-wi0-x22c.google.com ([2a00:1450:400c:c05::22c]) by magus.postgresql.org with esmtps (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1Ydf66-0001Av-5N for pgsql-performance@postgresql.org; Thu, 02 Apr 2015 13:23:53 +0000 Received: by wiaa2 with SMTP id a2so105151435wia.0 for ; Thu, 02 Apr 2015 06:23:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :message-id:references:to; bh=FyYi2FzlghLbFG3ZK6HecFidrmBEOL6WCKLo7vxCzCo=; b=JgBMzNdHELc0pPOqgZiAG7ec4CO+tOY/RgkufvnI5TpfB1u89PfVu3dpVCV+pWw77i /B5RtMVHUYgKVmonFuy3nwGjKZDuayvn2H7WDsoruCGgiF7+RjVi3PZJ6Rl4rCWqsKZW 8F4rBA4fgrMwBWR/gf2JzzIYYEz9LbLNeMqlXQVZRdacEWVRbSG1GBviu9C/2Rw3sEq6 j8QH568qmu+Ktq50miBAXqtKmSSgW0Y3Au/NBa6TTr02W+/1lw8Fe2RSyfctvzY5cp/z 682VouwrZLuEbY5ILnCxsEXP3FBNdfKDc4t3iUjUGqs44jXAAi3/zGRjndRTVy6R2OSY XPQw== X-Received: by 10.194.240.73 with SMTP id vy9mr96258779wjc.41.1427981027575; Thu, 02 Apr 2015 06:23:47 -0700 (PDT) Received: from [192.168.2.2] (2-230-140-245.ip202.fastwebnet.it. [2.230.140.245]) by mx.google.com with ESMTPSA id bx3sm7254295wjc.21.2015.04.02.06.23.40 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 02 Apr 2015 06:23:46 -0700 (PDT) Content-Type: multipart/alternative; boundary="Apple-Mail=_994A3F71-44D1-41B0-B9DB-C8184A26AF5B" Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: Can't get Dell PE T420 (Perc H710) perform better than a MacMini with PostgreSQL From: Pietro Pugni In-Reply-To: Date: Thu, 2 Apr 2015 15:23:37 +0200 Cc: pgsql-performance@postgresql.org Message-Id: <2EBBCD54-D3C8-436F-AF73-84EEF258AB70@gmail.com> References: <87131335.225702.1427941178942.JavaMail.root@fmed.uba.ar> To: Aidan Van Dyk X-Mailer: Apple Mail (2.1878.6) X-Pg-Spam-Score: -2.7 (--) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org --Apple-Mail=_994A3F71-44D1-41B0-B9DB-C8184A26AF5B Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Hi Aidan, > =20 > T420 > work_mem =3D 512MB > =20 > MacMini > work_mem =3D 32MB >=20 > So that is why the T420 does memory sorts and the mini does disk = sorts. >=20 > I'd start looking at why memory sorts on the T420 is so slow. Check = your numa settings, etc (as already mentioned). >=20 > For a drastic test, disable the 2nd socket on the dell, and just use = one (eliminate any numa/QPI costs) and see how it compares to the = no-numa MacMini. >=20 the command=20 dmesg | grep -i numa doesn=92t display me anything. I think T420 hasn=92t NUMA on it. Is = there a way to enable it from Ubuntu? I don=92t have immediate access to = BIOS (server is in another location). For QPI I don=92t know what to do. Please, can you give me more details? > If you want to see how bad the NUMA/QPI is, play with stream to = benchmark memory performance. With stream you refer to this: = https://sites.utexas.edu/jdm4372/tag/stream-benchmark/ ? Do you suggest = me some way to do this kind of tests? Thank you very much=20 Pietro --Apple-Mail=_994A3F71-44D1-41B0-B9DB-C8184A26AF5B Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252
Hi Aidan,

 
T420
work_mem =3D = 512MB
 
MacMini
work_mem =3D = 32MB

So that is why the T420 does memory sorts and the = mini does disk sorts.

I'd start = looking at why memory sorts on the T420 is so slow.   Check your = numa settings, etc (as already mentioned).

For a drastic = test, disable the 2nd socket on the dell, and just use one (eliminate = any numa/QPI costs) and see how it compares to the no-numa = MacMini.


the command 
dmesg | grep -i = numa
doesn=92t display me anything. I think T420 hasn=92t= NUMA on it. Is there a way to enable it from Ubuntu? I don=92t have = immediate access to BIOS (server is in another location).
For = QPI I don=92t know what to do. Please, can you give me more = details?

If you want to see how bad the NUMA/QPI is, play = with stream to benchmark memory performance.

With stream you refer to this: https://si= tes.utexas.edu/jdm4372/tag/stream-benchmark/ ? Do you suggest me = some way to do this kind of tests?

Thank you very = much 
 Pietro

= --Apple-Mail=_994A3F71-44D1-41B0-B9DB-C8184A26AF5B--