Red Hat Bugzilla – Bug 809583
Posix test failures on cifs mount
Last modified: 2015-12-01 11:45:32 EST
Created attachment 574912 [details]
Test results file
Description of problem:
I have run posix tests on cifs mounts - both dir cifs mount (XFS backend) and gluster volume cifs mount
Many of the tests fail on both the mount.
But there are some extra failures on the gluster volume cifs mount in link and mkfifo tests.
Attached is the test result for both mounts.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Configure samba and do a cifs mount of a dir and gluster volume
2. Run posix tests on both the mount points.
3. Compare the results
Some of link and mkfifo tests that are passing on backend dir is failing on gluster volume
Number of failures should be same for both mounts
Created attachment 574913 [details]
test results for backend dir cifs mount
This is not a gluster bug.
The extra failed tests are all tests that check times (ctime, atime, mtime) of files. This is caused because of the difference in granularity of timestamps between XFS and Samba. XFS has 1 ns granularity whereas samba uses 100ns granularity.
Since, the posix-compliance testsuite is configured for XFS, there is a possiblity of some time comparision tests to fail as the comparisions are done at a nanosecond level. Though there is a change in the timestamp on the backend XFS, Samba can mask this change because of its larger granularity. This will cause tests like the ones above to fail some of the times. This also means that the same tests may not fail all the time as there is a possiblity of change in timestamp being large enough that even samba will show a change in timestamp.
The solution would be to run a modified version of the test-suite, which has the timestamp comparision tests disabled, on cifs mounts.