From nobody Tue Jan 09 08:47:59 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 4T8Phm5Zcqz56m6Y for ; Tue, 9 Jan 2024 08:48:08 +0000 (UTC) (envelope-from olce@freebsd.org) Received: from smtp.freebsd.org (smtp.freebsd.org [IPv6:2610:1c1:1:606c::24b:4]) (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 4T8Phm561jz4GBy for ; Tue, 9 Jan 2024 08:48:08 +0000 (UTC) (envelope-from olce@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1704790088; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8u5c3kDd6q0YjKy4QQhskPARocNSG0j3A9qUxv3Egu0=; b=OAaSrmrAhlhy1O9lSzSWArgPii+OarYVSsKZ5g8Apa2dGoMAJ5QrX2qwy5GA4pLB943nKK OjNKYZt2yTB9efWyFm+/Wd4zcsukTBaq5uF5kuIfAm+NcHQBxLVFlNWuObfVW4sHxunfcx WUuI2J5XMtUFaOzx3BBau/46yPkkfM1CnGK1vpu5Pf9XVrgq2LbBFrnuGcZJabXjyrn4mF yhi6eu2/IUYz/ts9idOEMCkVoY+qqK0D1Z5Y40gZaTH4tMylbfmhCGYWkBvnTPPqGRVKK5 mXNOkdaVoCf4+Bvt/Wys7QfjanGGZlIQqr5g9w+dLB1qMSUQXp4OCeLMFGfY5A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1704790088; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8u5c3kDd6q0YjKy4QQhskPARocNSG0j3A9qUxv3Egu0=; b=dC6c3WltYehIPVm/A4g9U0gGje494p/BMvTGKcx3g71E+y5KY+tIGLLFecg+Xfrr1LCrNj TNXq1LKAY+CT+kfoQMnfA04rUrFUvoVESkmt8xjvHi15jsO6tmFkICZYfEqTe/FPJl2V9M +9axwDB9PNm1lOFSG3cARJvQk6/JtrIkbPed/FHrv7OMMTXUik8TeOomClDTWAa6Q8nXBU 09ExJDYi3cdyBLs69qrBzddYzhcHwhNMMLLQTyyfstp8oI1R8aILxvtEb3b1eeu6SRdSkF IoG5mjYWlGlVGt/WcjaOjjoRECCwlDdLDvzBPtCVwxbnVTON6cwDVyZlfqctAw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1704790088; a=rsa-sha256; cv=none; b=jUsa9s7s21kC57p647Uq0PXGgUoX9eTiWb5O7IUYjMcXGVBCzSFRKBTI+QfuGTV+jyIcNP CyfdxuB3JVpRXkt4PaHnAVV9XLcFlt87Bp08WgOeuQ8OE8abY96kybYJVGmg1E1RXLCH5k j2XuqA+fTk8B1AHkGDpHl9MuIAyRM4xmpazwNZ9FudNGwViBT7y9UNkC8sOtMJYvQ5GhRr idBl9WuqzgSgRDSu4eYs6j5DPlkf6WU3QfYaiAlx6wbZy6/ZuWFM5PcAS+TemyicLia7+9 4+MQRp2UCZnoyiSBrFKtzN/9Z45bEFskzNoszNOPam0sy6FwaHdn0BRWHb6o7g== 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 4T8Phm2YfLzJ6S for ; Tue, 9 Jan 2024 08:48:08 +0000 (UTC) (envelope-from olce@freebsd.org) From: Olivier Certner To: freebsd-current@freebsd.org Subject: Re: noatime on ufs2 Date: Tue, 09 Jan 2024 09:47:59 +0100 Message-ID: <6714298.qJWK8QVVMX@ravel> In-Reply-To: <2eabfb91-afc3-47f7-98b9-1a1791ae6e7d@app.fastmail.com> References: <2eabfb91-afc3-47f7-98b9-1a1791ae6e7d@app.fastmail.com> 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="nextPart28415695.QdLYigECfs"; micalg="pgp-sha384"; protocol="application/pgp-signature" --nextPart28415695.QdLYigECfs Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="UTF-8"; protected-headers="v1" From: Olivier Certner To: freebsd-current@freebsd.org Subject: Re: noatime on ufs2 Date: Tue, 09 Jan 2024 09:47:59 +0100 Message-ID: <6714298.qJWK8QVVMX@ravel> In-Reply-To: <2eabfb91-afc3-47f7-98b9-1a1791ae6e7d@app.fastmail.com> MIME-Version: 1.0 > Why not make noatime the default across the whole system? Outside of mbox why is recording access time actually useful? Exactly. I've never found any compelling reason in most uses to enable "atime", except perhaps local mail but as addressed in other answers it is a relic of the past mostly irrelevant today. And its drawbacks are well known and can be serious. The auditing use is not what I consider "normal" in the sense I suspect it concerns a small minority of users (maybe even tiny). Plus, serious auditing requires keeping a log (generally immutable) of accesses, i.e., more than a single time and, as pointed out in another answer, at least the ID of the user performing the access. Updating the access time field on files/directories doesn't address both. What "relatime" only gives you is a guarantee that you know that some file has been accessed at some point after its last modification (or creation), and that the access time is correct if precision is only a day. It also generally lowers I/O obviously, but not in some scenarios (file creation and subsequent read). So, to me, at this point, it still sounds more than a gimmick than something really useful. If someone has a precise use case for it and motivation, than of course please go ahead. In the short term, I'd vote for turning "atime" off by default. Thanks and regards. -- Olivier Certner --nextPart28415695.QdLYigECfs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. 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