On Mon, Aug 1, 2011 at 4:26 PM, Bruce Guenter <bruce@xxxxxxxxxxxxxx> wrote: > On Thu, Jul 28, 2011 at 04:28:04PM -0400, Chris Mason wrote: >> The slow performance is probably coming from reading in the metadata >> associated with the snapshot extents. The new readahead extentions from >> Arne should help once we've adapted them to it. The easiest way to make >> sure is to hit sysrq-w a few times while it is slow (or run a patched >> latencytop). > > We shut down the rsync backups for now, and are waiting for the > snapshots to complete deletion so we can unmount the filesystem to > reboot (missing kernel options for latencytop). In the mean time I hit > SysRq-W quite a number of times, and nothing is showing up in kernel The keystroke should be alt-sysrq-w. > messages. However, btrfs-cleaner and/or btrfs-transaction (sometimes > both, sometimes just one) have been running high in top, taking up all > the CPU time. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
