by Read an interesting discussion on the lkml list where Linus and friends talked about atime’s performance impacts (http://kerneltrap.org/node/14148). Ingo phrased the problem best with:
‘ For every file that is read from the disk, lets do a … write to
the disk! And, for every file that is already cached and which we
read from the cache … do a write to the disk! ‘
Solutions are to mount your file systems with the noatime, nodiratime options. The only time this may cause a problem is if you have a local mail spool (the mailer will not know that new email arrived) or possibly with some backup software. The list mentions speed increases of up to 50% on build performance.