[Gluster-users] GlusterFS behaviour on stat syscall with relatime activated

Simon Turcotte-Langevin
2016-02-03T16:42:56Z

Hi, we have multiple clusters of GlusterFS which are mostly alike. The typical
setup is as such:


-          Cluster of 3 nodes

-          Replication factor of 3

-          Each node has 1 brick, mounted on XFS with RELATIME and NODIRATIME

-          Each node has 8 disks in RAID 0 hardware

The main problem we are facing is that observation of the access time of a file
on the volume will update the access time.

The steps to reproduce the problem are:


-          Create a file (echo 'some data' > /mnt/gv0/file)

-          Touch its mtime and atime to some past date (touch -d 19700101
/mnt/gv0/file)

-          Touch its mtime to the current timestamp (touch -m /mnt/gv0/file)

-          Stat the file until atime is updated (stat /mnt/gv0/file)

o   Sometimes it's instant, sometimes it requires to execute the above
command a couple of time



On the IRC channel, I spoke to a developer (nickname ndevos) who said that it
might be a getxattr() syscall that could be called when stat() is called on a
replicated volume.



Anybody can reproduce this issue? Is it a bug, or is it working as intended? Is
there any workaround?



Thank you,

Simon
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