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 1kdWad-0006hL-HI for pgsql-hackers@arkaria.postgresql.org; Fri, 13 Nov 2020 10:45:59 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1kdWac-0004Oy-Fq for pgsql-hackers@arkaria.postgresql.org; Fri, 13 Nov 2020 10:45:58 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1kdWac-0004Oq-8g for pgsql-hackers@lists.postgresql.org; Fri, 13 Nov 2020 10:45:58 +0000 Received: from mail-wm1-x344.google.com ([2a00:1450:4864:20::344]) by makus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1kdWaZ-0008Es-L5 for pgsql-hackers@postgresql.org; Fri, 13 Nov 2020 10:45:57 +0000 Received: by mail-wm1-x344.google.com with SMTP id 10so7673034wml.2 for ; Fri, 13 Nov 2020 02:45:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=enterprisedb-com.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=GoeUMaqhah73yYeccyiwnIrY4XlCmcD0UboP3r3TxFk=; b=nvytyyYisPADpqN9em7NSJ+B1MAhO5w+yvmJ8Qlpuo5Vdy8nqksgU7loxKv6Qj2nuP DShMXuuR9QvBY+8Cui84zUUibIOEG8fJlA8Z87GPUfOHgM9A8jZptv8Bzq5aUMgzwej6 Y+3HXr3dOg703AuGPfgc9Wl7cfOHU6pyarTvni54gT26RKVC61+7pUF6rEIwnyMSfMl9 mGdEU5KEoIOrBLdKn+2rIz8oH4a7r1Okyz61zlhlEdSuBYlCLiJ1sxyFpTnkaMlOUrIg 1nfGvsniBfb/p2SAAFTSjk7KYlE5OFafzjvmL35De49ALaTLrhOMLnQSqR+D31AF1BDW UWpA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=GoeUMaqhah73yYeccyiwnIrY4XlCmcD0UboP3r3TxFk=; b=n5EqVKgxngSdrMi0H65E5XiZszT4Gs9g9HN8eaIcko/UCfCICyavNPxZDS4Bpvhe+w uQih/qGA99V2NvTZLNhrTWTJHhrqKY2xDHPct1hyaaPI2vt5G0JKIJzkNlYNYupVUhfu 8sq817dns8RjCAi4jjLFh6bUqmhkOqp/fGt8kk8HD1wz3O69bFNmjMbGcuKD2DY+Z7uw s4T3ViADT8VKd7t9j7MU8r2kV8ATq5QRinvH0ZymcSOgH4iAOqNCuapJxOgWzH/ReJPN SOEutc0TlNOzyteGnhVtBc/1wy7REcUO8vcoxNa9vKxdU/oN67iI9VSFbd/aiqWwNitJ sX4Q== X-Gm-Message-State: AOAM532rfFkllpH0xfe9V2iSnvpvMBWxBBDMc4kWEcp2NBViyl+dDFFX JAdAWggdWg88/ZFZYJw0+b/l7AywszWTYUfdwXrHc27JgFJguxcox3bb4o9vzIW3tQBtl7+KHtY ssYSMsJEYZupNEGtUxfP3cW1TWFMSqIAKQMkqm5C+K7Wbtt13mMKzUfdx5i3swfKs2I6cJ6RI3n tyqGHHqMwutZ2cN1c42iLWUIuQCFAchG+pV1L/9H6NLk+9leH0Xs4ZVNeFot9PX+HBaQQ7T4ZnT 9mNHdVJwkHE1weMFxWpgKMo+kfFJOHtwxdl/cxL X-Google-Smtp-Source: ABdhPJyn0tkaBB0BLrZ2ZjMVLEOOIULs7q573ZXh//gP/LAn/nU7IBBmKSBAQD73WT1uutUtHkcZ8Q== X-Received: by 2002:a05:600c:4147:: with SMTP id h7mr1839553wmm.186.1605264353395; Fri, 13 Nov 2020 02:45:53 -0800 (PST) Received: from [10.137.0.4] (ip-86-49-245-76.net.upcbroadband.cz. [86.49.245.76]) by smtp.gmail.com with ESMTPSA id x2sm4558014wru.44.2020.11.13.02.45.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 13 Nov 2020 02:45:52 -0800 (PST) Subject: Re: WIP: WAL prefetch (another approach) To: Thomas Munro , Tomas Vondra Cc: Stephen Frost , Dmitry Dolgov <9erthalion6@gmail.com>, David Steele , Andres Freund , Alvaro Herrera , pgsql-hackers References: <20200806104701.j3xnkczd6qelfnhj@development> <20200901131426.5lse2jlepm3uligv@development> <20200901141826.gbhqz664brtt4y2t@development> <20200908231235.lsgat5ni35h6odqt@development> <20201010112935.qrhm572v4djrjljo@development> From: Tomas Vondra Message-ID: <5437ce5b-d305-bd85-23ec-ddb15735d93f@enterprisedb.com> Date: Fri, 13 Nov 2020 11:45:51 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CLOUD-SEC-AV-Info: enterprisedb,google_mail,monitor X-CLOUD-SEC-AV-Sent: true X-Gm-Spam: 0 X-Gm-Phishy: 0 List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On 11/13/20 3:20 AM, Thomas Munro wrote: > > ... > > I'm not really sure what to do about achive restore scripts that > block. That seems to be fundamentally incompatible with what I'm > doing here. > IMHO we can't do much about that, except for documenting it - if the prefetch can't work because of blocking restore script, someone has to fix/improve the script. No way around that, I'm afraid. regards -- Tomas Vondra EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company