Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cv5Fh-00015I-Jw for pgsql-admin@arkaria.postgresql.org; Mon, 03 Apr 2017 16:54:49 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84_2) (envelope-from ) id 1cv5Fg-0006xP-KE for pgsql-admin@arkaria.postgresql.org; Mon, 03 Apr 2017 16:54:48 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1cv5Ff-0006xD-KI for pgsql-admin@postgresql.org; Mon, 03 Apr 2017 16:54:48 +0000 Received: from mail-qt0-x22c.google.com ([2607:f8b0:400d:c0d::22c]) by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84_2) (envelope-from ) id 1cv5Fc-0002C5-5N for pgsql-admin@postgresql.org; Mon, 03 Apr 2017 16:54:46 +0000 Received: by mail-qt0-x22c.google.com with SMTP id i34so117688832qtc.0 for ; Mon, 03 Apr 2017 09:54:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:references:in-reply-to:subject:date:message-id :mime-version:thread-index:content-language; bh=QJa8pwXKKe2cQmx3rsOvLAYOnMDWERRATLx+pdrtxy0=; b=Aqz/WFWtEDlC/uoj3Hq+dCPLDANwZYDDW/rckgXFyCZR5XrIXWcibAuiPrpwpRm7/J +fEZS4wKbgtECb7QP56aeMFOivH2htUgJjDMKyxKKGYYUV2gkXVUD0Whp00nYDlTDJeQ suS7F0wEaJ37JPeBgaeSdYZTBQXaMs6DAxTFymappr7p6mSFg0bUcokYLBiE2b3NDHen Npby+5vgB5aP+g3E96NDwd2mqrAWpkxazwmsz9bxEA8JbHLsqsahqKoD+uPAlq/emCCX QHJ4FfBq93dZyEDH5p2MCAWCff4V8wtYZT+e0z7vVf83X2tSkHlJt791eoCgyI/jJy0H sWXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:references:in-reply-to:subject:date :message-id:mime-version:thread-index:content-language; bh=QJa8pwXKKe2cQmx3rsOvLAYOnMDWERRATLx+pdrtxy0=; b=fX+lcEcwuv47Cm/CGyzJx2Q1CGm3UnZ7xJvx0i6Law75ggf3Mnf1BqmXeNGOp5GpkQ 0K84f1sbZ9J0tF4ftqKmqmh//nip9l0MI+IsQv4KiY3zWRNwZNb3NM8In3auqzHNLFTq KyUjdHC7YnhQz/gX2XzQ4Dc3h6K2JlMTXRPuy6RHAXs9/t0ovXZSue1NFEz+eB/icbMb t+V2lvr0KuTloezPjHTmqOLQZ3cQNIrU8dJUAukfN2Kh351RLxECMuCKYL4WAK8jv/oH ja6oQKpu4Mosdi9EhkKhHZiaauR0/JYYpit+Qa6h6eMfTZVtF5s2gR5dQVRTORBeaZYi jmrw== X-Gm-Message-State: AFeK/H1IGcH0Pv1MEuFwsm/xnobsSXJ+oCGVwoa/Prbeyv4jdFpN392KEMxZae+dla37Vw== X-Received: by 10.200.39.130 with SMTP id w2mr17214701qtw.260.1491238482029; Mon, 03 Apr 2017 09:54:42 -0700 (PDT) Received: from irylachi ([200.55.161.75]) by smtp.gmail.com with ESMTPSA id d67sm8210761qkg.23.2017.04.03.09.54.17 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 03 Apr 2017 09:54:41 -0700 (PDT) From: "Lazaro Garcia" To: "'David G. Johnston'" Cc: References: <001f01d2aa2d$1f9f27a0$5edd76e0$@gmail.com> In-Reply-To: Subject: Re: Help with bad performance with synchronous commit Date: Mon, 3 Apr 2017 12:54:11 -0400 Message-ID: <002901d2ac9a$ef691cb0$ce3b5610$@gmail.com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002A_01D2AC79.686119A0" X-Mailer: Microsoft Outlook 15.0 Thread-Index: AQFuVlWdhUo+nA1nmFNyISMTKOiVPQJk9sF2omld14A= Content-Language: es-mx X-Pg-Spam-Score: -0.7 (/) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-admin Precedence: bulk Sender: pgsql-admin-owner@postgresql.org This is a multipart message in MIME format. ------=_NextPart_000_002A_01D2AC79.686119A0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Thanks for the reply: =20 pgbench -U postgres -p 6432 -j 10 -c 500 -T 60 -h localhost -P 2 = pgbench (write test) =20 I have uninstalled 9.6 and installed postgresql 9.5.6 from Ubuntu repos. = These was de new results:=20 =20 transaction type: TPC-B (sort of) scaling factor: 200 query mode: simple number of clients: 500 number of threads: 10 duration: 60 s number of transactions actually processed: 236733 latency average: = 126.187 ms latency stddev: 152.347 ms tps =3D 3919.425981 (including = connections establishing) tps =3D 3919.945554 (excluding connections = establishing) =20 2 days later the test throws less results but constant. =20 transaction type: TPC-B (sort of) scaling factor: 200 query mode: simple number of clients: 500 number of threads: 10 duration: 60 s number of transactions actually processed: 76788 latency average: = 394.308 ms tps =3D 1268.044488 (including connections establishing) tps = =3D 1268.124718 (excluding connections establishing) =20 The iowait was between 15 and 25 percet when the test was runing: =20 =20 Is there any way to identify the cause of this differences? =20 How can I configure commit_delay and commit_siblings properly? =20 These are disk details: =20 -------------------------------------------------------------------------= --------------------------------------- =20