On Mon, Jan 28, 2013 at 03:45:23PM +0100, Pierre Beck wrote: > > >We probably want to start by simplifying/narrowing it down a bit - we > >can eliminate the possibility of the disk having anything to do with it > >and just use the SSD by forcing everything to writeback mode: > > > >For that you'll want to disable both sequential bypass (echo 0 > > >/sys/block/bcache/bcacheN/sequential_cutoff) and the congested > >thresholds - > >echo 0 > /sys/fs/bcache/<cache set>/congested_read_threshold_us, > >echo 0 > /sys/fs/bcache/<cache set>/congested_write_threshold_us > > > >After that (assuming you're also in writeback mode) all writes will be > >writeback writes until the device is more than half full of dirty data. > > > >Can you check if transactions are still getting lost in that setup? If > >so (I kind of expect they will be) we may have to do a bit of > >blktracing, but that'll really narrow down the possibilities. > > > > Yes, the most recent transactions are still lost. Think I figured out what's going on. Just had a chat with another kernel dev and figured out the flaw in my logic :P This is going to take some thought to fix, though it shouldn't be much code. I'll let you know when I think I have a fix. -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
