So the takeaway from this is that btrfs send doesn't work this way, I
can't copy a file with reflink=always and expect it to be diffed
correctly as in a parent-child situation or?
On 2019-02-17 04:11, Remi Gauvin wrote:
On 2019-02-16 3:08 p.m., Andrei Borzenkov wrote:
File size of "real" server.jar is not exact multiple of btrfs block size
(4096) which causes the last extent to be "incomplete". btrfs won't
clone extent in this case. You can trivially reproduce it by using the
same size in the first case (although exact extent distribution may be
different of course, in the worst case you get single extent which is
sent in full):
dd if=/dev/urandom of=A/dir/server.jar bs=1024 count=34625
Thank you. I thought I had tested one where I changed the file size,
(by altering the bs,) but I must have inadvertently created a file that
still divided by 4096, (or it got split into a second extent).