On Fri, Feb 27, 2015 at 5:03 AM, Mark Wu <wudx05@xxxxxxxxx> wrote: > > I am wondering how the value of journal_align_min_size gives impact on > journal padding. Is there any document describing the disk layout of > journal? Not much, unfortunately. Just looking at the code, the journal will align any writes which are at least as large as that parameter, apparently based on the page size and the target offset within the destination object. I think this is so that it's more conveniently aligned for transfer into the filesystem later on, whereas smaller writes can just get copied? -Greg _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com