does 'noatime' make sense for a read-only filesystem?

Question

mount -o remount,ro,noatime

As the title says - if the filesystem is actually read-only, does noatime have any affect?

score 3 · Answer 1 · answered Jun 11 '12 at 13:37

Short answer: No.

If the filesystem is mounted read-only, then the kernel module should be sufficiently smart to not even think about writing atime entries for accessed files, because that would constitute a ... write, which is verboten by the read-only status.

score 2 · Answer 2 · edited Jul 10 '12 at 21:16

2

No, read only means read only, if you told it to not write to it it will not write access times to it.

For more information, see man fstab.

edited Jul 10 '12 at 21:16

Tamara Wijsman

57,881

answered Oct 20 '11 at 11:18

ktf

2,387

score 0 · Answer 3 · answered Oct 18 '17 at 16:54

Possibly. Depending on the filesystem.

Actually things here are much more interesting and odd than you might think.

...

Mounting your NFS filesystems with noatime will reduce the number of NFS requests you make to the server.

https://utcc.utoronto.ca/~cks/space/blog/linux/NFSReadonlyAtime

score 0 · Answer 4 · answered Mar 03 '20 at 14:01

0

As you didn't specify an os.

I know that on certain systems ro mounted filesystem will still update the atime, unless you specify the noatime option.

Ro only means the user cant write not that the fs can't write.

So better safe than sorry.

answered Mar 03 '20 at 14:01

John Kearney

101

does 'noatime' make sense for a read-only filesystem?

4 Answers4