Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tvGjg-002wqD-CB for pgsql-general@arkaria.postgresql.org; Thu, 20 Mar 2025 14:19:04 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.94.2) (envelope-from ) id 1tvGig-002HoE-SC for pgsql-general@arkaria.postgresql.org; Thu, 20 Mar 2025 14:18:02 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tvGig-002Ho3-Ho for pgsql-general@lists.postgresql.org; Thu, 20 Mar 2025 14:18:02 +0000 Received: from mail-ot1-x32e.google.com ([2607:f8b0:4864:20::32e]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.96) (envelope-from ) id 1tvGif-0008hA-01 for pgsql-general@postgresql.org; Thu, 20 Mar 2025 14:18:01 +0000 Received: by mail-ot1-x32e.google.com with SMTP id 46e09a7af769-72bccda48cbso616713a34.1 for ; Thu, 20 Mar 2025 07:18:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1742480280; x=1743085080; darn=postgresql.org; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :from:to:cc:subject:date:message-id:reply-to; bh=57FCnInoXPNsLp+tFahRHthm+8UnMlsXzt/PSJsqIrk=; b=OTByRty23oBSjfXA3CH5t+sFqhMwv9M7ss681WGHNPjtbfALBfb0iYEnJoW0HV5XDS KpE/ZuJNCEye23r8JbYWOP5SYYXfYVjp91gsWWLREMG2aYkgDogf+6b6C+fhNL4TfGJM AgGPXHfelR14c/ArFh3PHGcBEW1rxTKd5fZ+ba+jNfCRag1HMLRq6li4PhES2rHbVFc1 BtYlDfQ8BQIO4WerGLnbBeQzAFkjLczBuXRMxA5nzyvHoETzM1MNiJH20t0W3o3PEXlk Kc5kb4gW0aOuflPDkOL/h31ITRaUD5T6jWeGfRZXNQSvq8SIlUR1qvTzPlLjMBdU570l bpLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1742480280; x=1743085080; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=57FCnInoXPNsLp+tFahRHthm+8UnMlsXzt/PSJsqIrk=; b=WjS1pL3a3VKuoL/1HA10nu79cDCPf4MVRKj+QwwrkCOS/aloYWHZBUrah3/zHfNo4b SI1c+etQN4C8H3HPvvl3DMEKcY/5XnnrhfJNUklp3jYOS+H3agJwExgxrfQBVeLrvasK u5QyUO3K0CAXZS9m7ycFko+bKX1vzGOhwo+CQ5r+grqVbksOeob4I83JPtTWq+r7GBrr Cak8FTHFwF/6xnqi8F9D1MQpUu1A2G7ZBJgqi3+ckZXQ7/VwR/OF11tAT2EtujHr5TET awPMOFlXvdcj7x/kYPQB6pfQtw4+Xu0j4VGDGAHVIgxBjgSJP25VMYHd2rZFFmploI6V uCZw== X-Gm-Message-State: AOJu0YzfAfsTFaq96RuC6znf4f4WbOygjOSK0ymN5UlHbBZbpZ07AZJ7 5zBhxrHLB/xV/l3hiYkGaTa+DlNd+Y88l5NJRFGr0VzSifncSJMMCzHLbWUK08G20tMoJxJOqsb WywYp+BijWK4PPSEaTjoBRdUYhPi/Gg== X-Gm-Gg: ASbGncurTFac4sldmubLD7V7MJKJ0bURerS1++hqno5ILCCnEjupneTC7W8CrXajhh3 Xg01lYs1irIXyGFlhNZ6/V4qH+jElims5FIvCDmOVUhUX0PvAJQBWrD9xIx4T3IhwqRsNiJNpam IZVphPG3KZwx4AWHrD5S3HEPEClIjPhEI2hs9+ewW5JtwHesqsITG0sc0IL77Ae4ZO9ceeQAg= X-Google-Smtp-Source: AGHT+IF5wzxvXIqomhLfxOcoXhN1esaYHxpFoRXIFdEc6oLMHjNd1Awu5Cfo+izI5Kdrz5J8iwni0ag06zi/Gtn4RGA= X-Received: by 2002:a05:6830:34a5:b0:72a:10ec:3637 with SMTP id 46e09a7af769-72bfbddbdd0mr5592408a34.15.1742480279266; Thu, 20 Mar 2025 07:17:59 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Ron Johnson Date: Thu, 20 Mar 2025 10:17:46 -0400 X-Gm-Features: AQ5f1JppQVA9iH9u4KlNIMG-V6KeHF03YF-Myi6m_4Qr4M8InrhRZmC6wiXQMTg Message-ID: Subject: Re: Export operation efficiency in read replica To: pgsql-general Content-Type: multipart/alternative; boundary="00000000000013008b0630c6ce74" List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --00000000000013008b0630c6ce74 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, Mar 20, 2025 at 7:52=E2=80=AFAM Siraj G wrote= : > Hello Experts! > > I have a DB with 1TB in size serving needs of one of our critical > applications. I have a requirement to take export of the DB on a daily > basis, but want to carry out this operation in read replica. The postgres= ql > version is: 16.6 > Use PgBackRest from the streaming replica. > What would be the RPO of such backup? > Are you asking how long it takes to restore the backup back to the primary? > What would be the impact on the READ REPLICA with a long running export > operation? > Why not use the standby server (aka "read replica") as the hot standby in case the Primary crashes hard? Then pg_basebackup (or PgBackRest) to get the database back to the primary once it's back up. --=20 Death to , and butter sauce. Don't boil me, I'm still alive. lobster! --00000000000013008b0630c6ce74 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Thu, Mar 20, 2025 at 7:52=E2=80=AFAM S= iraj G <tosiraj.g@gmail.com&g= t; wrote:
Hello Experts!
<= div>
I have a DB with 1TB in size serving needs of one of our= critical applications. I have a requirement to take export of the DB on a = daily basis, but want to carry out this operation in read replica. The post= gresql version is:=C2=A016.6

Use PgBackRest from the streaming = replica.
=C2=A0
What would = be the RPO of such backup?=C2=A0

Are you asking how long it takes to restore the backup back to the= primary?
=C2=A0
What would= be the impact on the READ REPLICA with a long running export operation?

Why not use the standby se= rver (aka "read replica") as the hot standby in case the Primary = crashes hard?

Then pg_basebackup (or PgBackRest) t= o get the database back to the primary once it's back up.
--
Death to <Redacted&g= t;, and butter sauce.
Don't boil me, I'm still alive.
<= div><Redacted> lobster!
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