On 29.03.2018 20:02, Alex Gorbachev wrote:
w Luminous 12.2.4 cluster with Bluestore, I see a good deal of scrub and deep scrub operations. Tried to find a reference, but nothing obvious out there - was it not supposed to not need scrubbing any more due to CRC checks?
crc gives you checks as you read data. iow you do not give corrupt data to clients, while thinking it is ok data. scrubs periodically checks your data for corruption, by reading it and comparing it to crc and the other replicas. this protects against bitrot [1] crc also helps the system to know what object is good and what object is bad during scrub.
crc is not a replacement for scrub, but a compliment. it improves the quality of the data you provide to clients, and it makes it easier for scrub to detect errors.
kind regards Ronny Aasen [ 1] https://en.wikipedia.org/wiki/Data_degradation _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
