Public bug reported: The libvirt driver is ignoring the 'disk_cachemodes' configuration setting and is always setting "cache='none'" in the device xml.
For example, with a setting in nova.conf of "disk_cachemodes=network=writeback": Expected result: # virsh dumpxml <instance> | grep cache <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> Actual result: # virsh dumpxml <instance> | grep cache <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> This is a regression in pike [1] that was also backported to ocata and newton. [1] https://review.openstack.org/#/c/485752 ** Affects: nova Importance: Undecided Assignee: melanie witt (melwitt) Status: In Progress ** Tags: libvirt -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1727558 Title: libvirt driver ignores 'disk_cachemodes' configuration setting Status in OpenStack Compute (nova): In Progress Bug description: The libvirt driver is ignoring the 'disk_cachemodes' configuration setting and is always setting "cache='none'" in the device xml. For example, with a setting in nova.conf of "disk_cachemodes=network=writeback": Expected result: # virsh dumpxml <instance> | grep cache <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> <driver name='qemu' type='raw' cache='writeback' discard='unmap'/> Actual result: # virsh dumpxml <instance> | grep cache <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> <driver name='qemu' type='raw' cache='none' discard='unmap'/> This is a regression in pike [1] that was also backported to ocata and newton. [1] https://review.openstack.org/#/c/485752 To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1727558/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
