23

I was trying to know if relatime or noatime was set on a filesystem, but i didn't found the information, neither in /etc/fstab, neither in kernel boot options.

First of all, it seems clear that i don't have the "normal" behaviour on atime:

root@antec:/tmp# rm -f test.txt; echo a>test.txt

root@antec:/tmp# stat test.txt | \grep -i 2011
Access: 2011-08-01 21:54:30.000000000 +0200
Modify: 2011-08-01 21:54:30.000000000 +0200
Change: 2011-08-01 21:54:30.000000000 +0200

root@antec:/tmp# cat test.txt > /dev/null

root@antec:/tmp# stat test.txt | \grep -i 2011
Access: 2011-08-01 21:54:53.000000000 +0200
Modify: 2011-08-01 21:54:30.000000000 +0200
Change: 2011-08-01 21:54:30.000000000 +0200

root@antec:/tmp# date
Mon Aug  1 21:55:00 CEST 2011

root@antec:/tmp# cat test.txt > /dev/null

root@antec:/tmp# stat test.txt | \grep -i 2011
Access: 2011-08-01 21:54:53.000000000 +0200 <--- atime not modified
Modify: 2011-08-01 21:54:30.000000000 +0200
Change: 2011-08-01 21:54:30.000000000 +0200
root@antec:/tmp#

I have two questions:
- Is noatime or relatime a default mount options, and if yes, from which kernel release ?
- Is there a way to see the default mount options (ie: how can i see why i don't have the "normal" atime behaviour ?)
Many questions but i think they are related. Feel free to edit the title if you have a more explicit title.

BenMorel
  • 1,011
user368507
  • 331

3 Answers3

23

This should list all the options a file system was mounted with:

cat /proc/mounts
Clarus
  • 813
3

This question is pretty old, but you can look at default mount options for an ext filesystem with:

tune2fs -l /dev/<device>
James Hewitt
  • 31
1

nfsstat -m will give you a listing of all NFS mounts and flags.

With that said, I had to use cat /proc/mounts on an older 2.6.5 kernel, since nfsstat -m wasn't supported then.

Banjer
  • 447