On Wed, Mar 2, 2016 at 9:05 AM, Zhi Zhang <zhang.david2011@xxxxxxxxx> wrote: > Hi Guys, > > Recently I am trying cache tier and if I try to stat a non-existent > object in both cache tier pool and base pool, I find cache tier will > not just return -ENOENT, but also create an empty object with setting > its flag as FLAG_WHITEOUT in cache tier pool. > > Although it indicates this object is not existed logically, why cache > tier will try to create it rather than only returning -ENOENT? I would imagine the logic is to cache the fact that the object doesn't exist, so that if the client repeatedly tries to fetch the non-existent object, it doesn't have to keep querying the backing pool to check. John > Thanks. > > Regards, > Zhi Zhang (David) > Contact: zhang.david2011@xxxxxxxxx > zhangz.david@xxxxxxxxxxx > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" 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 ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
