[PATCH v9 02/17] schema: Add new domain elements to support multiple throttle filters

From: Chun Feng Wu <danielwuwy(a)163.com&gt; Introduce schema for defining '<throttlefilters>' element which references throttling groups to form filter chain in qemu for specific disk * Add new elements '<throttlefilters>' * <ThrottleFilters> can include multiple throttlegroup references to form filter chain in qemu * Chained throttle filters feature in qemu is described at https://gitlab.com/qemu-project/qemu/blob/master/docs/throttle.txt Signed-off-by: Chun Feng Wu <danielwuwy(a)163.com&gt; Signed-off-by: Harikumar Rajkumar <harirajkumar230(a)gmail.com&gt; Reviewed-by: Peter Krempa <pkrempa(a)redhat.com&gt; Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- docs/formatdomain.rst | 21 +++++++++++++++++++++ src/conf/schemas/domaincommon.rng | 19 ++++++++++++++++++- 2 files changed, 39 insertions(+), 1 deletion(-) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index 1209c76995..8be0159230 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -2819,6 +2819,15 @@ paravirtualized driver is specified via the ``disk`` element. </backingStore> <target dev='vdh' bus='virtio'/> </disk> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2' /> + <source file='/var/lib/libvirt/images/disk.qcow2'/> + <target dev='vdh' bus='virtio'/> + <throttlefilters> + <throttlefilter group='limit2'/> + <throttlefilter group='limit012'/> + </throttlefilters> + </disk> </devices> ... @@ -3321,6 +3330,18 @@ paravirtualized driver is specified via the ``disk`` element. :since:`since after 0.4.4`; "sata" attribute value :since:`since 0.9.7`; "removable" attribute value :since:`since 1.1.3`; "rotation_rate" attribute value :since:`since 7.3.0` +``throttlefilters`` + The optional ``throttlefilters`` element provides the ability to provide additional + per-device throttle chain :since:`Since 11.2.0` + For example, if we have four different disks and we want to limit I/O for each one + and we also want to limit combined I/O of all four disks, we can leverage + ``throttlefilters`` to achieve this goal by setting two ``throttlefilter`` for + each disk: disk's own filter(e.g. limit2) and combined filter(e.g. limit012). + The order of such ``throttlefilter`` doesn't matter within ``throttlefilters``. + ``throttlefilters`` and ``iotune`` should be used exclusively. + + ``throttlefilter`` + The optional ``throttlefilter`` element is to reference defined throttle group. ``iotune`` The optional ``iotune`` element provides the ability to provide additional per-device I/O tuning, with values that can vary for each device (contrast diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng index 25eb195635..ae2d0daad3 100644 --- a/src/conf/schemas/domaincommon.rng +++ b/src/conf/schemas/domaincommon.rng @@ -1630,7 +1630,10 @@ <ref name="encryption"/> </optional> <optional> - <ref name="diskIoTune"/> + <choice> + <ref name="throttlefilters"/> + <ref name="diskIoTune"/> + </choice> </optional> <optional> <ref name="alias"/> @@ -6885,6 +6888,20 @@ </element> </optional> </define> + <!-- + A set of throttlefilters to reference throttlegroups + --> + <define name="throttlefilters"> + <element name="throttlefilters"> + <zeroOrMore> + <element name="throttlefilter"> + <attribute name="group"> + <data type="string"/> + </attribute> + </element> + </zeroOrMore> + </element> + </define> <!-- A set of optional features: PAE, APIC, ACPI, GIC, TCG, HyperV Enlightenment, KVM features, paravirtual spinlocks and HAP support -- 2.48.1