Description of problem:
The man page for mount incorrectly describes the mount option relatime;
Update inode access times relative to modify or change time. Access time is only updated if the previous access time was ear-
lier than the current modify or change time. (Similar to noatime, but doesn’t break mutt or other applications that need to
know if a file has been read since the last time it was modified.)
However, this is incorrect. The code in the kernel will update the atime if it is more than 24 hours later than mtime;
* With relative atime, only update atime if the previous atime is
* earlier than either the ctime or mtime or if at least a day has
* passed since the last atime update.
static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
struct timespec now)
if (!(mnt->mnt_flags & MNT_RELATIME))
* Is mtime younger than atime? If yes, update atime:
if (timespec_compare(&inode->i_mtime, &inode->i_atime) >= 0)
* Is ctime younger than atime? If yes, update atime:
if (timespec_compare(&inode->i_ctime, &inode->i_atime) >= 0)
* Is the previous atime value older than a day? If yes,
* update atime:
if ((long)(now.tv_sec - inode->i_atime.tv_sec) >= 24*60*60)
* Good, we can skip the atime update:
It is worth mentioning that more recent versions of the man mount page state the correct behaviour.
Update inode access times relative to modify or change time. Access time is only updated if the previous access time was earlier than the
current modify or change time. (Similar to noatime, but doesn't break mutt or other applications that need to know if a file has been read
since the last time it was modified.)
Since Linux 2.6.30, the kernel defaults to the behavior provided by this option (unless noatime was specified), and the strictatime option
is required to obtain traditional semantics. In addition, since Linux 2.6.30, the file's last access time is always updated if it is
more than 1 day old.
(taken from util-linux 2.20.1)
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. man mount
2. read entry for "relatime"
Incorrectly describes relatime option
Should correctly describe relatime option
This request was not resolved in time for the current release.
Red Hat invites you to ask your support representative to
propose this request, if still desired, for consideration in
the next release of Red Hat Enterprise Linux.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.