Am Montag, 25. April 2016, 08:28:45 schrieb Bart Van Assche: > On 04/25/2016 05:10 AM, Philipp Reisner wrote: > > If during resync we read only zeroes for a range of sectors assume > > that these secotors can be discarded on the sync target node. > > Hello Phil, > > With which interconnect(s) has this patch been tested? I'm afraid that > for high-speed interconnects this patch will slow down I/O instead of > making it faster because all_zero() examines all data before it is sent. >
Hi Bart, that it might make things slower is true for sure. The benefit it provides is to de-allocate blocks on the secondary obviously. The whole feature is optional and it is off by default. Obviously we want to have a generic interface like SEEK_HOLE/ SEEK_DATA for block devices, but that does not exist as of today. best regards, Phil
