Hi Clemens, On Wed, 2014-01-15 at 12:44 +0100, Clemens Eisserer wrote: > Hi Vyacheslav, > > > The main approach of NILFS2 is COW (copy-on-write) policy. It means that > > all data and metadata are written in log manner. Only superblocks are > > placed in fixed positions and updated there. First superblock is located > > in the volume begin, second one in the volume end. > > Can you give me an estime how often the superblock is updated / written to? > NILFS2 has special method nilfs_sb_need_update() [1] and special constant NILFS_SB_FREQ [2] that it is used usually for definition frequency of superblocks updating. So, as far as I can judge, default value of such frequency under high I/O load is 10 seconds (Minimum interval of periodical update of superblocks (in seconds)). With the best regards, Vyacheslav Dubeyko. [1] http://lxr.free-electrons.com/source/fs/nilfs2/the_nilfs.h#L254 [2] http://lxr.free-electrons.com/source/fs/nilfs2/the_nilfs.h#L252 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
