ext4 defaults and access time

[Patrick O'Callaghan]

On Tue, 2010-02-02 at 20:54 +0100, Andras Simon wrote:
> All my partitions are ext4 and mounted with ext4 defaults from fstab.
> Still, sometimes it's as if noatime was used:
> 
> [simon at pici uffi]$ date
> Tue Feb  2 20:48:22 CET 2010
> [simon at pici uffi]$ cat clsql-uffi-loader.lisp > /dev/null
> [simon at pici uffi]$ ls -lu clsql-uffi-loader.lisp
> -rw-rw-r--. 1 simon simon 2995 2010-02-02 16:24 clsql-uffi-loader.lisp
> 
> Can it be some caching issue? If so, is there a way to force ls -lu to
> show the last access time, independently of whether that involves
> physical access?

The last access time is the last access time is the last access time.
IOW there's no concept of a "physical" access time different from what
ls is showing you. Caching between RAM and the physical medium is
completely transparent at this level.

(I note that the file mode above includes a "." so it appears to have
extended attributes, if that helps at all).

poc