The /sys/block/bcache0/bcache/stats_total/bypassed should accumulate (notice the stats_total), but stats_day only shows results with an exponentially weighted average with a half life of 1 day. If your load varies during the day, the amount bypassed will swing up and down accordingly. Adam On Thu, Jan 26, 2012 at 10:31 AM, David Rhodes Clymer <david@xxxxxxxxxxxxxx> wrote: > > Although the doc (Documentation/bcache.txt) seems to indicate that > "bypassed" should contain cumulative IO for the stat period, I've > noticed that it does not consistently increase. In fact, it increases > and decreases quite a bit over a short period of time. > > root@zapazoid:~# date > Thu Jan 26 13:23:34 EST 2012 > root@zapazoid:~# cat /sys/block/bcache0/bcache/stats_day/bypassed > 5.4M > root@zapazoid:~# cat /sys/block/bcache0/bcache/stats_day/bypassed > 9.1M > root@zapazoid:~# cat /sys/block/bcache0/bcache/stats_day/bypassed > 1008k > root@zapazoid:~# cat /sys/block/bcache0/bcache/stats_day/bypassed > 2.4M > root@zapazoid:~# cat /sys/block/bcache0/bcache/stats_day/bypassed > 5.1M > root@zapazoid:~# date > Thu Jan 26 13:24:44 EST 2012 > > > This is while doing an rsync into a cached filesystem, which I would > imagine would entail a significant amount of sequential writes. > > Am I just misunderstanding what this is supposed to be telling me? > > -davidc > -- > 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 -- 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
