On Wed, May 06, 2015 at 03:19:13PM -0700, Sage Weil wrote: > > Just out of curiosity, if you need to modify the application anyway, > > why wouldn't use of fdatasync() when flushing be able to offer a > > similar performance boost? > > Although fdatasync(2) doesn't have to update synchronously, it does > eventually get written, and that can trigger lots of unwanted IO. Something that might be worth trying out is using MS_LAZYTIME plus fdatasync(2). That should significantly reduce the unwanted IO, while eventually letting the mtimes get updated, plus allowing updates of adjacent inodes in the same inode table block update the mtime "for free". Regards, - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
