• Lars Ellenberg's avatar
    drbd: implement csums-after-crash-only · aaaba345
    Lars Ellenberg authored
    Checksum based resync trades CPU cycles for network bandwidth,
    in situations where we expect much of the to-be-resynced blocks
    to be actually identical on both sides already.
    
    In a "network hickup" scenario, it won't help:
    all to-be-resynced blocks will typically be different.
    
    The use case is for the resync of *potentially* different blocks
    after crash recovery -- the crash recovery had marked larger areas
    (those covered by the activity log) as need-to-be-resynced,
    just in case. Most of those blocks will be identical.
    
    This option makes it possible to configure checksum based resync,
    but only actually use it for the first resync after primary crash.
    Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
    Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
    aaaba345
drbd_limits.h 6.92 KB