Cinder

  1. Bug #1472486
  2. Comment #4

Comment 4 for bug 1472486

Revision history for this message
OpenStack Infra (hudson-openstack) wrote : Fix merged to cinder (master)

Reviewed: https://review.openstack.org/200237
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=8a944bc8573eee775de8ea983191e0a4e808aaba
Submitter: Jenkins
Branch: master

commit 8a944bc8573eee775de8ea983191e0a4e808aaba
Author: Mitsuhiro Tanino <email address hidden>
Date: Thu Jul 9 16:04:25 2015 -0400

    LVM: Support efficient data copy for LVM driver

    The create_volume_from_snapshot() and migrate_volume() use
    dd command for data copy, but the copy always copies full blocks
    even if the source data contains many null or zero blocks.
    When we use thin provisioned LVM, blocks are not pre-allocated,
    so unused region returns zero.
    If we copy full block for destination volume, unnecessary blocks
    will be allocated and the usage will be 100%.

    The dd command has conv=sparse option in order to copy data more
    efficiently. This patch enables conv=sparse option for
    create_volume_from_snapshot() and migrate_volume() when we use
    thin provisioned LVM.

    Change-Id: I104c4127bc4a33da9c11ad2aac93766f862e2981
    Closes-bug: #1472486