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Would the remount command do it if I add the option in /etc/fstab?

Is this this a good idea?

ckliborn
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    Good idea? Not always. Prefer `relatime` where available. – Ignacio Vazquez-Abrams Jan 04 '12 at 02:38
  • @IgnacioVazquez-Abrams Why? I've equally read people saying 'prefer `noatime` unless you use the approximately 1 program that thinks it needs `[rel]atime`'. I have no reason to care about access time, so I'm turning it off. – underscore_d Jun 12 '16 at 19:52
  • For me it is always good idea to use `noatime`. I never needed the `atime` attribute value from any single file. I believe this attribute is one of the worst and useless things anyone ever added in Linux. – Victor Yarema Mar 31 '22 at 12:22

3 Answers3

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Yes, it would work.
Or you can manually add it like:

mount -o remount,noatime /dev/sd0 /mnt
Mattias Ahnberg
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    With many versions of mount you can omit either the device or the mount point (your choice) and it will lookup the other. – tylerl Jan 04 '12 at 02:37
  • Who said anything about `/mnt`? OP wanted to remount their `/` fs. I sure hope this command would stop some theoretical naive copy-paste reader from remounting their root filesystem at `/mnt` and thus, presumably, killing their entire session. I'm not about to test that theory, though! – underscore_d Jun 12 '16 at 19:55
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Edit /etc/fstab and add the proper noatime entry to your / filesystem entry.

Remount the / filesystem with:

mount -o remount,noatime /

ewwhite
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  • How can I verify that the noatime functionality is in place after the remount? Also do I need to worry about anything when remounting /? – ckliborn Jan 04 '12 at 05:56
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    You can look at `/proc/mounts` to see the flags currently in effect. – Simon Richter Jan 04 '12 at 07:18
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    Type `mount`. It will show the mount parameters. – ewwhite Jan 04 '12 at 09:38
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    @ckliborn you can also test it by yourself: 1. pick a file that is not being read or written by anybody, 2. check its atime with `ls -lu` and make sure it's some time in the past, 3. read it with `cat` or `cksum`, 4. check its atime again and it should not have changed. – Tobia Jul 04 '14 at 08:49
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Not anymore. -o remount,noatime was an effective method of disabling atime without a reboot.

I don't know that I'd say it's a good idea, but if you intend to turn atime off, I don't see what it would be a bad idea either if you have an old enough kernel. According to the man page for mount:

MS_REMOUNT

The following mountflags can be changed: MS_RDONLY, MS_SYNCHRONOUS, MS_MANDLOCK; before kernel 2.6.16, the following could also be changed: MS_NOATIME and MS_NODIRATIME; and, additionally, before kernel 2.4.10, the following could also be changed: MS_NOSUID, MS_NODEV, MS_NOEXEC.

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Jeff Ferland
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