Hmm, since you seem to be able to reproduce the problem reliably, any chance you can try bisecting the problem? I've looked at the commits that touch fs/jbd2 and nothing is jumping out at me. Also, how many CPU's do you have your system, and what kind of storage device were you using when you were running iozone (5400rpm HDD, 7200RPM HDD, RAID array, SSD, etc.)? Thanks, - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html