Dong Yuan <yuandong <at> unitedstack.com> writes: > > Hi Sage, > > I am now working with the BP osd: update Transaction encoding, but the > Transaction::get_data_alignment make me confused. > > This method give the alignment which is used by FileJournal to do > better buffer build. It calculate the alignment by largest_data_off > and get_data_offset() while the first is an offset of some object and > the second is an offset of the transaction encode result. I am not > sure there is any reason to do calculation between them. > > The code works fine, probably because any result is fine for > Transaction::get_data_alignment, while > FileJournal::prepare_single_write can use any alignment value to build > logical bufferlist. > > Can you give me some explanation? Thank you. > Hi, i send a pull request to reduce the memcopy cause by unalignment. https://github.com/ceph/ceph/pull/2803 I think get_data_offset() should not care largest_data_off. Jianpeng Thanks! -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
