Re: [PATCH Libvirt v2 00/10] Support dirty page rate upper limit

Hi, This is the latest version for the series, comparing with version 1, there are some key modifications has made inspired and suggested by Peter, see as follows: 1. Introduce XML for dirty limit persistent configuration 2. Merge the cancel API into the set API 3. Extend the domstats/virDomainListGetStats API for dirty limit information query 4. Introduce the virDomainModificationImpact flags to control the behavior of the API 5. Enrich the comments and docs about the feature and API The patch set introduce the new API virDomainSetVcpuDirtyLimit to allow upper Apps to set upper limits of dirty page rate for virtual CPUs, the corresponding virsh API as follows: # limit-dirty-page-rate <domain> <rate> [--vcpu <number>] \ [--config] [--live] [--current] We put the dirty limit persistent info with the "vcpus" element in domain XML and extend dirtylimit statistics for domGetStats: <domain> ... <vcpu current='2'>3</vcpu> <vcpus> <vcpu id='0' hotpluggable='no' dirty_limit='10' order='1'.../> <vcpu id='1' hotpluggable='yes' dirty_limit='10' order='2'.../> </vcpus> ... If --vcpu option is not passed in the virsh command, set all virtual CPUs; if rate is set to zero, cancel the upper limit. Examples: To set the dirty page rate upper limit 10 MB/s for all virtual CPUs in c81_node1, use: [root@srv2 my_libvirt]# virsh limit-dirty-page-rate c81_node1 --rate 10 --live Set dirty page rate limit 10(MB/s) for all virtual CPUs successfully [root@srv2 my_libvirt]# virsh dumpxml c81_node1 | grep dirty_limit <vcpu id='0' enabled='yes' hotpluggable='no' order='1' dirty_limit='10'/> <vcpu id='1' enabled='yes' hotpluggable='no' order='2' dirty_limit='10'/> <vcpu id='2' enabled='yes' hotpluggable='no' order='3' dirty_limit='10'/> <vcpu id='3' enabled='no' hotpluggable='yes' dirty_limit='10'/> <vcpu id='4' enabled='no' hotpluggable='yes' dirty_limit='10'/> ...... Query the dirty limit info dynamically: [root@srv2 my_libvirt]# virsh domstats c81_node1 --dirtylimit Domain: 'c81_node1' dirtylimit.vcpu.0.limit=10 dirtylimit.vcpu.0.current=0 dirtylimit.vcpu.1.limit=10 dirtylimit.vcpu.1.current=0 dirtylimit.vcpu.2.limit=10 dirtylimit.vcpu.2.current=0 dirtylimit.vcpu.3.limit=10 dirtylimit.vcpu.3.current=0 dirtylimit.vcpu.4.limit=10 dirtylimit.vcpu.4.current=0 ...... To cancel the upper limit, use: [root@srv2 my_libvirt]# virsh limit-dirty-page-rate c81_node1 \ --rate 0 --live Cancel dirty page rate limit for all virtual CPUs successfully [root@srv2 my_libvirt]# virsh dumpxml c81_node1 | grep dirty_limit [root@srv2 my_libvirt]# virsh domstats c81_node1 --dirtylimit Domain: 'c81_node1' The dirty limit uses the QEMU dirty-limit feature introduced since 7.1.0, this feature allows CPU to be throttled as needed to keep their dirty page rate within the limit. It could, in some scenes, be used to provide quality-of-service in the aspect of the memory workload for virtual CPUs and QEMU itself use the feature to implement the dirty-limit throttle algorithm and apply it on the live migration, which improve responsiveness of large guests during live migration and can result in more stable read performance. The other application scenarios remain unexplored, before that, Libvirt could provide the basic API. Please review, thanks Yong Hyman Huang(黄勇) (10): qemu_capabilities: Introduce QEMU_CAPS_VCPU_DIRTY_LIMIT capability conf: Introduce XML for dirty limit configuration libvirt: Add virDomainSetVcpuDirtyLimit API qemu_driver: Implement qemuDomainSetVcpuDirtyLimit domain_validate: Export virDomainDefHasDirtyLimitStartupVcpus symbol qemu_process: Setup dirty limit after launching VM virsh: Introduce limit-dirty-page-rate api qemu_monitor: Implement qemuMonitorQueryVcpuDirtyLimit qemu_driver: Extend dirtlimit statistics for domGetStats virsh: Introduce command 'virsh domstats --dirtylimit' docs/formatdomain.rst | 7 +- docs/manpages/virsh.rst | 33 +++- include/libvirt/libvirt-domain.h | 5 + src/conf/domain_conf.c | 26 +++ src/conf/domain_conf.h | 8 + src/conf/domain_validate.c | 33 ++++ src/conf/domain_validate.h | 2 + src/conf/schemas/domaincommon.rng | 5 + src/driver-hypervisor.h | 7 + src/libvirt-domain.c | 68 +++++++ src/libvirt_private.syms | 1 + src/libvirt_public.syms | 5 + src/qemu/qemu_capabilities.c | 2 + src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_driver.c | 181 ++++++++++++++++++ src/qemu/qemu_monitor.c | 25 +++ src/qemu/qemu_monitor.h | 22 +++ src/qemu/qemu_monitor_json.c | 107 +++++++++++ src/qemu/qemu_monitor_json.h | 9 + src/qemu/qemu_process.c | 44 +++++ src/remote/remote_driver.c | 1 + src/remote/remote_protocol.x | 17 +- src/remote_protocol-structs | 7 + .../qemucapabilitiesdata/caps_7.1.0_ppc64.xml | 1 + .../caps_7.1.0_x86_64.xml | 1 + tests/qemucapabilitiesdata/caps_7.2.0_ppc.xml | 1 + .../caps_7.2.0_x86_64+hvf.xml | 1 + .../caps_7.2.0_x86_64.xml | 1 + .../caps_8.0.0_riscv64.xml | 1 + .../caps_8.0.0_x86_64.xml | 1 + .../qemucapabilitiesdata/caps_8.1.0_s390x.xml | 1 + .../caps_8.1.0_x86_64.xml | 1 + tools/virsh-domain-monitor.c | 7 + tools/virsh-domain.c | 109 +++++++++++ 34 files changed, 737 insertions(+), 4 deletions(-) -- 2.38.5