On Jul 16, 2007 13:02 +0800, Stuart Midgley wrote: > Is the atime of a file stored on the mds or on an ost? I can imagine > positive and negatives with both approaches.
Both, to some extent. The OSTs store a "transient" atime that is updated when clients do read requests. The permanent atime is written to the MDS when the file is closed, but only changes the on-disk atime if it is more than 60s (/proc/fs/lustre/mds/*/max_atime_diff) old. The latest atime wins. If a setattr comes in, it is updated on both the MDS and OST, allowing the atime to go backward. Cheers, Andreas -- Andreas Dilger Principal Software Engineer Cluster File Systems, Inc. _______________________________________________ Lustre-discuss mailing list [email protected] https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
