Ceph » CephFS

Sorry but I think we need to re-open this.

On v12.2.8 ceph-fuse client and server, we see the exact same behaviour (modifying file contents does not change parent dir rctime):

> touch rober3/test_file
> getfattr -n ceph.dir.rctime rober3
# file: rober3
ceph.dir.rctime="1536159033.0992199201" 

> echo "content" >> rober3/test_file
> getfattr -n ceph.dir.rctime rober3
# file: rober3
ceph.dir.rctime="1536159033.0992199201" 

> touch rober3/test_file2
> getfattr -n ceph.dir.rctime rober3
# file: rober3
ceph.dir.rctime="1536159060.0926720137" 

> echo "content" >> rober3/test_file
> getfattr -n ceph.dir.rctime rober3
# file: rober3
ceph.dir.rctime="1536159060.0926720137" 

Dan van der Ster wrote:

Sorry but I think we need to re-open this.

On v12.2.8 ceph-fuse client and server, we see the exact same behaviour (modifying file contents does not change parent dir rctime):

[...]

Dan, did you try calling fsync and/or waiting some time before checking the rctime? The rstats are propagated lazily and the client updates on the inode need sync'd before checking in any case.

Patrick Donnelly wrote:

Dan van der Ster wrote:

Sorry but I think we need to re-open this.

On v12.2.8 ceph-fuse client and server, we see the exact same behaviour (modifying file contents does not change parent dir rctime):

[...]

Dan, did you try calling fsync and/or waiting some time before checking the rctime? The rstats are propagated lazily and the client updates on the inode need sync'd before checking in any case.

Hi Patrick. I called sync, waited 10 minutes, and still the parent dir (rober3) rctime doesn't move. I even remounted to make sure the contents were flushed. I also failed over both active mds's but that doesn't update the rctime.

Here are some additional tests. Note that updating the entire file contents (with >) does update the rctime of the parents. Append (>>) apparently does not.

[09:10]> mkdir -p a/b
[09:11]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304279.09539255733" 

[09:11]> echo content > a/b/test_file
[09:11]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304303.09489060210" 

[09:11]> echo content2 > a/b/test_file
[09:11]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304313.09320979663" 

All good so far. Let's try append.

[09:11]> echo content2 >> a/b/test_file
[09:12]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304313.09320979663" 

[09:12]> ls -l a/b/
total 1
-rw-r--r--. 1 root root 18 Sep  7 09:12 test_file
[09:12]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304313.09320979663" 

[09:12]> sleep 300
[09:19]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304313.09320979663" 

With >> rctime never updates, even after sleeping 5 minutes and ls.

Now overwrite the file again:

[09:19]> ls -i a/b/test_file
1099992134357 a/b/test_file
[09:22]> echo content > a/b/test_file
[09:22]> ls -i a/b/test_file
1099992134357 a/b/test_file
[09:22]> getfattr -n ceph.dir.rctime a
# file: a
ceph.dir.rctime="1536304956.09726248438" 

When we > it updates the parents' rctime correctly.

I just noticed that the qa test added in this PR doesn't check the >> case.

qa/workunits/fs: test for cephfs rstats