Bug 1381416

Following is the RCA(in my environment I included one of Dan's fix[1] )

While running the bonnie test , the one of readdir call got failed due to bad cookie error. Hence test resulted in failure.
Cause (assumed) :
The last readdir call should return mdcache_avl_lookup_k() MDCACHE_AVL_LAST, but it returning MDCACHE_AVL_NO_ERROR and following readdir results in bad cookie error.

[1] https://review.gerrithub.io/#/c/298859/

The readdir calls works based on cookie value. It is kind of offset value. For example, if we need to read 1000 directory entries, client will send lots of readdir call and on each readdir call the value of cookie will be incremented.

Here incase of Bonnie test after doing the creates, reads, stats etc it will try to delete the test dir. As part of this removal operation client sends a readdir calls. It goes smoothly and read all the contents & then client again sends another call with a previous cookie value(don't know the reason why client send so), MDCACHE layer(in ganesha) complains it is a BADCOOKIE. bonnie test fails with this error and tries to clean up test dir(again it fails with directory NOTEMPTY error). Please note after this when we directly deletes the same test directory from mount point it works fine.

Explanation from Frank why MDCACHE returns BADCOOKIE error( from IRC logs) :
 MDCACHE populates the entire directory from FSAL in one go, then it feeds protocol layer from dirent cache, when protocol layer has a subsequent request with a non-zero cookie, MDCACHE uses that cookie (which is the dirent hash key) to find the dirent that can break if the directory mutates

If understand correctly , cookie used MDCACHE cannot passed to upper FSAL layer(libgfapi). i.e it is not possible to forward a single readdir request(which is failed in MDCACHE) to FSAL layer.

Solution should be used readdir call based FSAL_COOKIE

Executed bonnie test in the latest build,

glusterfs-ganesha-3.8.4-5.el7rhgs.x86_64
nfs-ganesha-gluster-2.4.1-1.el7rhgs.x86_64

And fails with the same error.

executing bonnie
Using uid:0, gid:0.
Writing a byte at a time...done
Writing intelligently...done
Rewriting...done
Reading a byte at a time...done
Reading intelligently...done
start 'em...done...done...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...Bonnie: drastic I/O error (rmdir): Directory not empty
Cleaning up test directory after error.

real	34m8.225s
user	0m2.673s
sys	1m18.910s
bonnie failed
0
Total 0 tests were successful
Switching over to the previous working directory
Removing /mnt/test_nfs//run1183/
rmdir: failed to remove ‘/mnt/test_nfs//run1183/’: Directory not empty
rmdir failed:Directory not empty

As mentioned in #C11 , I also see following error with bonnie:

Changing to the specified mountpoint
/mnt/nfs/run16037
executing bonnie
Using uid:0, gid:0.
Writing a byte at a time...done
Writing intelligently...done
Rewriting...done
Reading a byte at a time...done
Reading intelligently...done
start 'em...done...done...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...Bonnie: drastic I/O error (rmdir): Directory not empty
Cleaning up test directory after error.

real	27m49.168s
user	0m1.347s
sys	0m32.871s
bonnie failed
0
Total 0 tests were successful
Switching over to the previous working directory
Removing /mnt/nfs/run16037/
rmdir: failed to remove ‘/mnt/nfs/run16037/’: Directory not empty
rmdir failed:Directory not empty



When trying manually using rm -rf it removes the directory successfully.
may be we need to check with script maintainer or debug more on nfs-client issue.

Hi Soumya,

I have edited the known issues doc text further. Let me know if there is anything specific that needs to be added as a workaround

Hi Bhavana,
Doc text looks good to me.

address test suite issues?

LGTM