Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lDN2a-0004Va-1d for pgsql-hackers@arkaria.postgresql.org; Sat, 20 Feb 2021 07:51:00 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1lDN2X-0006uo-EJ for pgsql-hackers@arkaria.postgresql.org; Sat, 20 Feb 2021 07:50:57 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lDN2X-0006ug-51 for pgsql-hackers@lists.postgresql.org; Sat, 20 Feb 2021 07:50:57 +0000 Received: from mail-pf1-x433.google.com ([2607:f8b0:4864:20::433]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1lDN2T-0001Hn-AP for pgsql-hackers@postgresql.org; Sat, 20 Feb 2021 07:50:55 +0000 Received: by mail-pf1-x433.google.com with SMTP id t29so3370502pfg.11 for ; Fri, 19 Feb 2021 23:50:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=p4A0kIr48MiAJVLqAjm7NfK6gtJ1WE6kl6PdFFQVGpg=; b=hzRrdcy9wNHO0VC6Dxy7/rpcXM4FZOlWyaY/Pq8sckkfvckF1/82XDZVjIuwHICKNB EH6q0U457Mvd76XSmxo6kn1W4o1LBHGR/86UObG4imsuDRST9cKv5zQRT4H3BaKhLHpv c9qcS2BUDgVLYDaEag3P6o+ShgYGf22l1f+OlhgL0wAykf1ud+kSaLXW1rlvtb/h+kTq +zFNAhRYucT20xqR8jkAL8+BKQTW0yFiTNqlsWPXyjt2hCcNeOVjNNe4kWF+3Y4IFeJT ON3bbh7zdJUss8tdno4kBDRBNAYMEcJq7e8JF30Ml3neM8M4Ps+wZ68cIYattmP+z7N9 RPow== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=p4A0kIr48MiAJVLqAjm7NfK6gtJ1WE6kl6PdFFQVGpg=; b=obxkqRfRktzp3fEsdXKRKIJEh7LtI3CnhGnmOngloyhZa9ZFcMdqr0pI+rJtlYpbY5 V2gKyQfh0PndIHgEZJepYCxiF1stcl7c3dTTH2Mzit/dn7ZXK6mXou0EzGA3MI3tyP7E A8t0Z7eAClIYjtuZRRFiqfhG3cAUYumcuYtyudOR07a14SHTSPYLhdN4JKpDxTfSff/7 1Bygmq4PW6yezQM+OrloFPiQVb92zR1QTj0IqG4TR1lxyL+woDT6K6UIjbopMzGhzRRP Ulc7BHAQL434bdq3/WYehns5QRSKelHF+9J1RdRNaLGoEWzJNmorJxLYmpy3L1bWid/O v+TA== X-Gm-Message-State: AOAM533N91WRGqdD9ACAqcZMYQZkj+p+1wFXWfqs3WyGlWntRF0zhiGA F45mSOq47E2fUl7WXSwo/e2yL/oWi6YT67gFwK4= X-Google-Smtp-Source: ABdhPJz/4Zj6hE0jMhMrsdQ9D0yzQnBtRB7o5Ge8DdbSm2HH1Q3HsbleOMwuUQw5tsZZqpxXiVp634QXZbk839icgmg= X-Received: by 2002:a62:1ad1:0:b029:1e8:228e:1cf5 with SMTP id a200-20020a621ad10000b02901e8228e1cf5mr12965470pfa.58.1613807450510; Fri, 19 Feb 2021 23:50:50 -0800 (PST) MIME-Version: 1.0 References: <20201217050522.GU30237@telsasoft.com> <20201217204442.GX30237@telsasoft.com> <20201218175439.GA30237@telsasoft.com> <20201221074725.GF30237@telsasoft.com> <20201225023958.GW30237@telsasoft.com> <96eaa813-4ad6-e80a-04a4-cc8082d356dd@swarm64.com> <508af801-6356-d36b-1867-011ac6df8f55@swarm64.com> In-Reply-To: From: Bharath Rupireddy Date: Sat, 20 Feb 2021 13:20:39 +0530 Message-ID: Subject: Re: New Table Access Methods for Multi and Single Inserts To: Zhihong Yu Cc: Luc Vlaming , Justin Pryzby , PostgreSQL-development , Andres Freund , Paul Guo , Jeff Davis Content-Type: text/plain; charset="UTF-8" List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On Sat, Feb 20, 2021 at 12:53 PM Zhihong Yu wrote: > > Hi, > bq. case 3 - 2 integer(of 4 bytes each) columns, tuple size 32 bytes > > Is there some other column(s) per row apart from the integer columns ? Since the 2 integer columns only occupy 8 bytes. I wonder where the other 32-8=24 bytes come from. There are no other columns in the test case. Those 24 bytes are for tuple header(23bytes) and 1 byte for other bookkeeping info. See "Table Row Layout" from https://www.postgresql.org/docs/devel/storage-page-layout.html. With Regards, Bharath Rupireddy. EnterpriseDB: http://www.enterprisedb.com