Hi, There's something I don't understand about the exclusive-lock feature.
I created an image: $ ssh host-3 Container Linux by CoreOS stable (1298.6.0) Update Strategy: No Reboots host-3 ~ # uname -a Linux host-3 4.9.9-coreos-r1 #1 SMP Tue Mar 14 21:09:42 UTC 2017 x86_64 Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz GenuineIntel GNU/Linux host-3 ~ # rbd create test-xlock --size=1024 --image-feature exclusive-lock host-3 ~ # rbd feature enable test-xlock exclusive-lock rbd: failed to update image features: (22) Invalid argument2017-03-21 10:16:50.911598 7f6975ff0100 -1 librbd: one or more requested features are already enabled I mapped it host-3 ~ # rbd map --options lock_on_read test-xlock /dev/rbd0 I also could map it from another host (disappointment started here): host-2 ~ # rbd map --options lock_on_read test-xlock /dev/rbd9 I can read from both host: host-2 ~ # dd if=/dev/rbd9 of=/dev/null 2097152+0 records in 2097152+0 records out 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 4.61844 s, 232 MB/s host-3 ~ # dd if=/dev/rbd0 of=/dev/null 2097152+0 records in 2097152+0 records out 1073741824 bytes (1.1 GB, 1.0 GiB) copied, 3.33527 s, 322 MB/s And also write: host-3 ~ # dd if=/dev/urandom of=/dev/rbd0 bs=1M count=1 1+0 records in 1+0 records out 1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.0153388 s, 68.4 MB/s host-2 ~ # dd if=/dev/urandom of=/dev/rbd9 bs=1M count=1 1+0 records in 1+0 records out 1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.0312396 s, 33.6 MB/s Isn't exclusive-lock supposed to forbid at least concurrent writes? _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
