[ceph-users] Re: Deep-scrub much slower than HDD speed

Hi all,

Scrubs only read data that does exist in ceph as it exists, not every sector of the drive, written or not.

Thanks, this does explain it. I just discovered: ZFS had this problem in the past: * https://utcc.utoronto.ca/~cks/space/blog/solaris/ZFSNonlinearScrubs?showcomm... OpenZFS solved it in 2017, using two-phase scrubs: * https://github.com/openzfs/zfs/issues/3625 * https://github.com/openzfs/zfs/commit/d4a72f23863382bdf6d0ae33196f5b5decbc48... Perhaps Ceph can use the same approach; I filed https://tracker.ceph.com/issues/59584 for it.