mount -o remount,ro,noatime
As the title says - if the filesystem is actually read-only, does noatime have any affect?
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.
No, read only means read only, if you told it to not write to it it will not write access times to it.
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