From nobody Sun Jan 14 16:38:32 2024 X-Original-To: freebsd-current@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4TCgvG6v2Pz56cBC for ; Sun, 14 Jan 2024 16:38:34 +0000 (UTC) (envelope-from olce@freebsd.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4TCgvG5vRPz4KFD; Sun, 14 Jan 2024 16:38:34 +0000 (UTC) (envelope-from olce@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1705250314; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xCirQMuVhknDBD/5o80ZS3bh7yqwPfVoPFDYK1CKMdA=; b=KZiYEtWu36/4buHEyAso/bJ3Uf3JFHmi/x4tPcwb55EhJMvnb3ozsD9xOAdFRghdFCoW1p 0TFqIbmCvAmJGKfGcI1SU+kXnNtA4ge0r+7NvpGE9o8r4oMmWVrtxGHFqY4t+lNWmaBK/x vyhwRXNoTpfwymnVeQXYKycwM0RvFAN//pcO3jywNGClU46K+lVwk3G8Mh2A3ValPJBQJV t6dVb/AvtwhF/H12rePEA2+V81q8zvr3T05lhzcCRNxSd5+L5o2cI9XYUihsosQ6oOB84q ifcWqcTg2AJjnLfsVITgKhd09YLrk4y1tmzDyI8y5Ma1RQUJd3l3N3OqfFmM4A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1705250314; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=xCirQMuVhknDBD/5o80ZS3bh7yqwPfVoPFDYK1CKMdA=; b=fAw8ugLZLXwi7Necjsv49ga43MKvT+7fGPrvYR4BawPwFhGuc0WYioYP/qMEBcBwLL9qn6 fxAcsxsmShFQPtkNTSGFFNd/vr2AGWBgSm3hRwR/z/P2jb2b0D5QP29+C17jiY9RKR0FA1 arW4qJ9Cq7e2FxAIpC2vO2L55NnlfH7VURiCuykk8YP3+qMIQ4nkCd48q8hYPYvsCOzW3P IMk1o1XcU/4arjq+9NnJ1AuAp3jfqqTWLaxI8EX0wm5P20P1SQxVEE3CvZQqPKGBKFGn8A Ke7wfhrzQNlMbCLuQqZvUdVJDsRgAAz5CN/OHC6gB633bVmb0hLKCk+QYZARxw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1705250314; a=rsa-sha256; cv=none; b=awoBidzrfWc+VYUPqLNf9KR3WvdUitwfwhIhdSppFgoA+V34kZvXSB5WmuT9QPskbJN9wi u6AJYlaWJq7cpiv0QAnz5o9RphGtoaBaN69qlra/3i2FGMG+Wck3XSfG269QUVVS65yKTA 8D9rRrtL08bqiCrgqftyFBg6OAvQy97HGN4Cvnl784PwDSLUHCryJVWyOGEmDe8A9uhXLT WsprvKNL/QyJ+hZZ8ixqkvkX4OPtSaG8ytCPJ4VL/vg0AK1whTr7SyIHuAphw6s9cE44mS rEm4jkUPIm9ek942gSkZRhZNxEfOnk19T2pkZM7UX2uo4ylEGCRpBS0DVYYC/g== Received: from ravel.localnet (lfbn-nic-1-525-172.w90-118.abo.wanadoo.fr [90.118.140.172]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: olce/mail) by smtp.freebsd.org (Postfix) with ESMTPSA id 4TCgvG2pnjz156f; Sun, 14 Jan 2024 16:38:34 +0000 (UTC) (envelope-from olce@freebsd.org) From: Olivier Certner To: Jamie Landeg-Jones Cc: freebsd-current@freebsd.org Subject: Re: noatime on ufs2 Date: Sun, 14 Jan 2024 17:38:32 +0100 Message-ID: <3172137.KEUK7n9DnO@ravel> In-Reply-To: <202401111956.40BJuURB045685@donotpassgo.dyslexicfish.net> References: <2136329.mxFCRLsXLg@ravel> <202401111956.40BJuURB045685@donotpassgo.dyslexicfish.net> List-Id: Discussions about the use of FreeBSD-current List-Archive: https://lists.freebsd.org/archives/freebsd-current List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-current@freebsd.org MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1775136.nRgdb1dTNT"; micalg="pgp-sha384"; protocol="application/pgp-signature" --nextPart1775136.nRgdb1dTNT Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="UTF-8"; protected-headers="v1" From: Olivier Certner To: Jamie Landeg-Jones Cc: freebsd-current@freebsd.org Subject: Re: noatime on ufs2 Date: Sun, 14 Jan 2024 17:38:32 +0100 Message-ID: <3172137.KEUK7n9DnO@ravel> MIME-Version: 1.0 Hi Jamie, > I've often wished there was the ability to set a process to "noatime" - where > all accesses to the filesytem by the process and its children don't alter > atime. It would be handy for those cases you describe above, such as backups > and locate, but these days, where it matters, and is suitable, I instead > create a filesystem snapshot, and run the process on that instead. (which is > how "live" backups should be done anyway!) I've mentioned your answer in another response to Lyndon Nerenberg when developing a more general argument that 'atime' is generally flawed for these kinds of use cases (finding the last use, finding files to backup, etc.). It's true that the ability to deactivate 'atime''s implicit updates per-process would cater to more use cases, and it's an interesting idea. Essentially, though, you can't guarantee that some applications, or simply administrators typing commands at the shell, are not going to throw away your precious access times, so can't rely (in a strong sense) on them. Sure for backups and snapshots. I agree you'd better have backup perimeters coinciding with file systems partitions and use snapshots to get the smoothest possible experience. But snapshots alone do not guarantee the "correctness" of a backup (the ability to restart smoothly from it). Cheers. -- Olivier Certner --nextPart1775136.nRgdb1dTNT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. 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