[Drbd-dev] Querying the devel plan of speed up initial sync of new and empty devices

[Nick Wang]

Hi,

DRBD is quite important and useful in SUSE HA product.
With the feedback from customer, the initial sync will took some time 
even if no 'real' data has to be synced, especially with huge devices.
Although the DRBD device can be fully operational with performance 
reduced before the initial synchronization has completed.

A method that can be used in SUSE HA 12 SP1 is under evaluation. 
One draft idea is to set a "a zeroed device" flag in metadata when 
using "drbdadm primary --force --<zeroed device flag> <res>", 
then the secondary device can skip the data sync but zeroing the 
device locally.

Comparing to the full sync, the data can be zerod without sync(only 
metadata synced). And compare to only sync the metadata, there 
is not necessary to the admin to guarantee all remote device are 
zerod/new already.

Before starting to do it. I want to ask is there any plan of the similar 
feature in upstream? And if not, can i work on it for both upstream 
and SUSE?

Since I am not an expert of DRBD yet like you, any suggestion or idea 
will be appreciate and helpful. Thanks in advanced.

# Since DRBD9 GM is not ready yet, the first target of 
development is drbd.8.4.x

Best regards,
Nick