Hi, I've been experimenting with using cephfs to set the object/stripe size on a Ceph filesystem root, and it seems to not persist across a filesystem restart. Is that expected behavior? To reproduce on current testing branch (6d0dc4bf6): --- # create a new filesystem, mount it; then # from a client: [root@an1024 ~]# df -h /mnt/ceph Filesystem Size Used Avail Use% Mounted on 172.17.40.34:/ 13T 510M 13T 1% /ram/mnt/ceph [root@an1024 ~]# cephfs /mnt/ceph/ show_layout layout.data_pool: 0 layout.object_size: 4194304 layout.stripe_unit: 4194304 layout.stripe_count: 1 layout.preferred_osd: -1 [root@an1024 ~]# cephfs /mnt/ceph set_layout -s 262144 -c 1 -u 262144 [root@an1024 ~]# cephfs /mnt/ceph/ show_layout layout.data_pool: 0 layout.object_size: 262144 layout.stripe_unit: 262144 layout.stripe_count: 1 layout.preferred_osd: -1 [root@an1024 ~]# touch /mnt/ceph/test1 [root@an1024 ~]# cephfs /mnt/ceph/test1 show_layout layout.data_pool: 0 layout.object_size: 262144 layout.stripe_unit: 262144 layout.stripe_count: 1 layout.preferred_osd: -1 [root@an1024 ~]# umount /mnt/ceph [root@an1024 ~]# mount.ceph an14-ib0:/ /mnt/ceph [root@an1024 ~]# df -h /mnt/ceph Filesystem Size Used Avail Use% Mounted on 172.17.40.34:/ 13T 178M 13T 1% /ram/mnt/ceph [root@an1024 ~]# cephfs /mnt/ceph/ show_layout layout.data_pool: 0 layout.object_size: 262144 layout.stripe_unit: 262144 layout.stripe_count: 1 layout.preferred_osd: -1 --- OK, so far. After filesystem unmount/shutdown/restart/mount: --- [root@an1024 ~]# df -h /mnt/ceph Filesystem Size Used Avail Use% Mounted on 172.17.40.34:/ 13T 450M 13T 1% /ram/mnt/ceph [root@an1024 ~]# cephfs /mnt/ceph/ show_layout layout not specified --- Hmmm, not what I was expecting. Also: --- [root@an1024 ~]# cephfs /mnt/ceph/test1 show_layout layout.data_pool: 0 layout.object_size: 262144 layout.stripe_unit: 262144 layout.stripe_count: 1 layout.preferred_osd: -1 [root@an1024 ~]# touch /mnt/ceph/test2 [root@an1024 ~]# cephfs /mnt/ceph/test2 show_layout layout.data_pool: 0 layout.object_size: 4194304 layout.stripe_unit: 4194304 layout.stripe_count: 1 layout.preferred_osd: -1 --- Also not what I was expecting. I thought my 256 KiB setting from before should still be in effect. Am I missing something? Thanks -- Jim -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
