Hi all, For a given file in cephfs, I would like to determine: 1) the number of PGs 2) the PG IDs 3) the offsets handles by each PG 4) the stripe unit (i.e. bytes per block of data) preferably using a C API. I found the getfattr command line tool which provides (1) and (4). It appears that cephfs command line tool provides some of the info, but the manpage is not clear as to what is provided by show_layout versus show_location. Does show_layout provide (1) and (4)? Does show_location include (2) and (3)? I found a Java CephFileExtent() that provides (1) and a list of OSDs for the stripe unit that contains the provided file extent. On the architecture page (http://ceph.com/docs/next/architecture/) under DATA STRIPING, does cephfs client use the same set of PGs used for Object Set 1 for Object Set 2 or does it use a different PGs? Scott ======================================= Scott Atchley HPC Systems Engineer Oak Ridge Leadership Computing Facility atchleyes@xxxxxxxx -- 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
