Re: [PATCH RFC v2 00/12] Support throttle block filters

From: Chun Feng Wu <wucf(a)linux.ibm.com&gt; Hi, I am thinking to leverage "throttle block filter" in QEMU to support more flexible I/O limits(e.g. tiered I/O groups), one sample provided by QEMU doc is: https://github.com/qemu/qemu/blob/master/docs/throttle.txt "For example, let's say that we have three different drives and we want to set I/O limits for each one of them and an additional set of limits for the combined I/O of all three drives." The implementation idea is to - Define throttle groups(limit) in domain - Define throttle filter to reference throttle group within disk - Within domain disk, throttle filters references multiple throttle groups to form filter chain to apply multiple limits in QEMU like above sample - Add new virsh cmds for throttle group management: throttlegroupset Add or update a throttling group. throttlegroupdel Delete a throttling group. throttlegroupinfo Get a throttling group. throttlegrouplist list all domain throttlegroups - Update "attach-disk" to add one more option "--throttle-groups" to apply throttle filters e.g. "virsh attach-disk $VM_ID ${DISK_PATH}/vm1_disk_2.qcow2 vdd --driver qemu --subdriver qcow2 --targetbus virtio --throttle-groups limit2,limit012" - I chose above semantics as I felt they're appropriate, if there are better ones please kindly suggest. This patchset includes: - Throttle group and throttle filter definition in patch 1 - New QMP processing to update and get throttle group in patch 2 - New API definition and implementation in patch 3 - QEMU driver implementation in patch 4 - Hotplug and qemuProcessLaunch flow implemenation in patch 5,6 - Domain XML schema and doc(formatdomain.rst) change in patch 7 - Tests in patch 8,9 - Virsh cmd implementation in patch 10 - Other verification implementation in patch 11, 12 v2 changes: - fix failure caused by "check-remote_protocol" between patch 3 and patch 9 in v1 - make sure coding style is consistent about function declaration - patch 3 in v1 is splitted into two commits: "remote: New APIs for ThrottleGroup lifecycle management" and "qemu: Implement qemu driver for throttle API" - replace "// comment" with "/* comment */" - avoid empty 'cleanup' labels - use "virJSONValueObjectAdd(&limits, "P:name", value)" to avoid introducing extra helper, and check return value - preserve spacing between blocks of code which are not related - remove "VSH_OT_ALIAS" section for new cmds in virsh_domain.c From QMP perspective, the sample flow works this way: - Throttle group creation: virsh qemu-monitor-command 1 '{"execute":"object-add", "arguments":{"qom-type":"throttle-group","id":"limit0","limits":{"iops-total":200,"iops-read":0,"iops-total-max":200,"iops-total-max-length":1}}}' virsh qemu-monitor-command 1 '{"execute":"object-add", "arguments":{"qom-type":"throttle-group","id":"limit1","limits":{"iops-total":250,"iops-read":0,"iops-total-max":250,"iops-total-max-length":1}}}' virsh qemu-monitor-command 1 '{"execute":"object-add", "arguments":{"qom-type":"throttle-group","id":"limit2","limits":{"iops-total":300,"iops-read":0,"iops-total-max":300,"iops-total-max-length":1}}}' virsh qemu-monitor-command 1 '{"execute":"object-add", "arguments":{"qom-type":"throttle-group","id":"limit012","limits":{"iops-total":400,"iops-read":0,"iops-total-max":400,"iops-total-max-length":1}}}' - Chain up filters during attaching disk to apply two filters(limit0 and limit012): virsh qemu-monitor-command 1 '{"execute":"blockdev-add", "arguments": {"driver":"file","filename":"/virt/disks/vm1_disk_1.qcow2","node-name":"test-3-storage","auto-read-only":true,"discard":"unmap"}}' virsh qemu-monitor-command 1 '{"execute":"blockdev-add", "arguments":{"node-name":"test-3-format","read-only":false,"driver":"qcow2","file":"test-3-storage","backing":null}}' virsh qemu-monitor-command 1 '{"execute":"blockdev-add", "arguments":{"driver":"throttle","node-name":"libvirt-5-filter","throttle-group": "limit0","file":"test-3-format"}}' virsh qemu-monitor-command 1 '{"execute":"blockdev-add", "arguments": {"driver":"throttle","node-name":"libvirt-6-filter","throttle-group":"limit012","file":"libvirt-5-filter"}}' virsh qemu-monitor-command 1 '{"execute": "device_add", "arguments": {"driver":"virtio-blk-pci","scsi":false,"bus":"pci.0","addr":"0x5","drive":"libvirt-6-filter","id":"virtio-disk1"}}' Any comments/suggestions will be appriciated! Chun Feng Wu (10): config: Introduce ThrottleGroup and ThrottleFilter qemu: monitor: Add support for ThrottleGroup operations remote: New APIs for ThrottleGroup lifecycle management qemu: Implement qemu driver for throttle API qemu: hotplug: Support hot attach block disk along with throttle filters qemu: command: Support throttle groups and filters during qemuProcessLaunch schema: Add new domain elements to support multiple throttle filters test: Test throttle group lifecycle APIs tests: Test qemuMonitorJSONGetThrottleGroup and qemuMonitorJSONUpdateThrottleGroup virsh: Add support for throttle group operations Hao Ning Xin (1): config: validate: Verify throttle group fields Yan Xiu Wu (1): config: validate: Use "iotune" and "throttlefilters" exclusively for specific disk docs/formatdomain.rst | 48 ++ include/libvirt/libvirt-domain.h | 29 + src/conf/domain_conf.c | 386 +++++++++++++ src/conf/domain_conf.h | 54 ++ src/conf/domain_validate.c | 120 ++-- src/conf/schemas/domaincommon.rng | 164 +++++- src/conf/virconftypes.h | 4 + src/driver-hypervisor.h | 22 + src/libvirt-domain.c | 190 +++++++ src/libvirt_private.syms | 9 + src/libvirt_public.syms | 7 + src/qemu/qemu_block.c | 131 +++++ src/qemu/qemu_block.h | 53 ++ src/qemu/qemu_command.c | 158 ++++++ src/qemu/qemu_command.h | 9 + src/qemu/qemu_domain.c | 85 +++ src/qemu/qemu_domain.h | 15 + src/qemu/qemu_driver.c | 529 ++++++++++++++++++ src/qemu/qemu_hotplug.c | 24 + src/qemu/qemu_monitor.c | 34 ++ src/qemu/qemu_monitor.h | 14 + src/qemu/qemu_monitor_json.c | 151 +++++ src/qemu/qemu_monitor_json.h | 14 + src/remote/remote_daemon_dispatch.c | 61 ++ src/remote/remote_driver.c | 49 ++ src/remote/remote_protocol.x | 50 +- src/remote_protocol-structs | 30 + src/test/test_driver.c | 382 +++++++++++++ tests/qemumonitorjsontest.c | 88 +++ .../qemustatusxml2xmldata/backup-pull-in.xml | 1 + .../blockjob-blockdev-in.xml | 1 + .../blockjob-mirror-in.xml | 1 + .../migration-in-params-in.xml | 1 + .../migration-out-nbd-bitmaps-in.xml | 1 + .../migration-out-nbd-out.xml | 1 + .../migration-out-nbd-tls-out.xml | 1 + .../migration-out-params-in.xml | 1 + tests/qemustatusxml2xmldata/modern-in.xml | 1 + tests/qemustatusxml2xmldata/upgrade-out.xml | 1 + .../qemustatusxml2xmldata/vcpus-multi-in.xml | 1 + tools/virsh-completer-domain.c | 64 +++ tools/virsh-completer-domain.h | 10 + tools/virsh-domain.c | 471 ++++++++++++++++ 43 files changed, 3430 insertions(+), 36 deletions(-)