LU-12988 osd: do not use preallocation during mount
as cold mballoc cache can cause very lengthy search.
Lustre-commit:
ae21fce625ec6cd134fa4764683f00bc692132cb
Lustre-change: https://review.whamcloud.com/36704
Change-Id: I821b023d392336f0085a96e821dc22e92dbf23b7
Signed-off-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Li Xi <lixi@ddn.com>
Reviewed-on: https://review.whamcloud.com/37155
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>