MonitorProtocol
QEMU Monitor Protocol
The QEMU Monitor Protocol (QMP) allows applications to communicate with QEMU's Monitor.
QMP is JSON-based, its main features are:
- Lightweight, text-based, easy to parse data format
- Asynchronous events support
The README file explains how to use it and its full specification can be found here.
General Status
A preview version of QMP is available in QEMU version 0.12.
However, QMP is still under development being considered unstable and incomplete. For more information about converted handlers, please check #Conversion Status.
Examples
In the following examples, 'C' stands for 'Client' and 'S' stands for 'Server'.
Server Greeting
S: {"QMP": {"capabilities": []}}
Query version
C: { "execute": "query-version" }
S: {"return": {"qemu": "0.11.50", "package": ""}}
Eject a device
C: { "execute": "eject", "arguments": { "device": "ide1-cd0" } }
S: {"return": {}}
Development
Primary contact is Luiz Capitulino, but all QMP-related discussions happen on the qemu-devel mailing list.
Next features, hot fixes and other patches are stored in the QMP unstable repository:
http://repo.or.cz/w/qemu/qmp-unstable.git
NOTE: all branches in this repository are constantly rebased (master inclusive).
TODO
- Convert all remaining commands
- High-level protocol documentation
- High-level internal documentation
- Improve internal API, currently it's too low-level
- Feature negotiation (?)
- Asynchronous commands support
- Better QObjects and QMP debug support
- Array-based Monitor's command table
- Libqmp
Conversion Status
UPDATED: 2009-12-16
| Command | Info | |
| Handlers | 62 | 36 |
| Converted | 19 | 15 |
| Percentage | 30% | 41% |
The following tables have a per-function status. There is one table for command handlers and another one for info handlers.
Status can be:
- merged: already merged upstream
- converted: converted but not merged yet
- partial: merged, but error handling is incomplete
NOTE: Handlers used by Libvirt are marked with yellow.
Command handlers
| Handler name | Status | Version | Comments |
| do_acl_add() | |||
| do_acl_policy() | |||
| do_acl_remove() | |||
| do_acl_reset() | |||
| do_acl_show() | |||
| do_balloon() | merged | 0.12 | |
| do_boot_set() | |||
| do_change() | merged | 0.12 | |
| do_closefd() | merged | 0.12 | |
| do_commit() | |||
| do_cont() | merged | 0.12 | |
| do_cpu_set() | |||
| do_delvm() | |||
| do_device_add() | |||
| do_device_del() | |||
| do_eject() | merged | 0.12 | |
| do_gdbserver() | |||
| do_getfd() | merged | 0.12 | |
| do_help_cmd() | |||
| do_info() | merged | 0.12 | as 'query-' commands |
| do_inject_mce() | |||
| do_inject_nmi() | |||
| do_ioport_read() | |||
| do_ioport_write() | |||
| do_loadvm() | |||
| do_log() | |||
| do_logfile() | |||
| do_memory_dump() | |||
| do_memory_save() | partial | 0.12 | |
| do_migrate() | partial | 0.12 | |
| do_migrate_cancel() | merged | 0.12 | |
| do_migrate_set_downtime() | |||
| do_migrate_set_speed() | merged | 0.12 | |
| do_mouse_button() | |||
| do_mouse_move() | |||
| do_mouse_set() | |||
| do_pci_device_hot_remove() | partial | 0.12 | |
| do_physical_memory_dump() | |||
| do_physical_memory_save() | partial | 0.12 | |
| do_print() | |||
| do_quit() | merged | 0.12 | |
| do_savevm() | |||
| do_screen_dump() | |||
| do_sendkey() | |||
| do_set_link() | |||
| do_singlestep() | |||
| do_stop() | merged | 0.12 | |
| do_stop_capture() | |||
| do_sum() | |||
| do_system_powerdown() | merged | 0.12 | |
| do_system_reset() | merged | 0.12 | |
| do_usb_add() | |||
| do_usb_del() | |||
| do_watchdog_action() | |||
| do_wav_capture() | |||
| drive_hot_add() | |||
| net_host_device_add() | |||
| net_host_device_remove() | |||
| net_slirp_hostfwd_add() | |||
| net_slirp_hostfwd_remove() | |||
| pci_device_hot_add() | partial | 0.12 |
Info handlers
| Handler name | Status | Version | Comments |
| bdrv_info() | merged | 0.12 | |
| bdrv_info_stats() | merged | 0.12 | |
| do_info_balloon() | merged | 0.12 | |
| do_info_capture() | |||
| do_info_cpus() | merged | 0.12 | |
| do_info_cpu_stats() | |||
| do_info_history() | |||
| do_info_hpet() | merged | 0.12 | |
| do_info_jit() | |||
| do_info_kvm() | merged | 0.12 | |
| do_info_mice() | merged | 0.12 | |
| do_info_migrate() | merged | 0.12 | |
| do_info_name() | merged | 0.12 | |
| do_info_network() | |||
| do_info_numa() | |||
| do_info_profile() | |||
| do_info_qdm() | |||
| do_info_qtree() | |||
| do_info_registers() | |||
| do_info_roms() | |||
| do_info_snapshots() | |||
| do_info_status() | merged | 0.12 | |
| do_info_usernet() | |||
| do_info_uuid() | merged | 0.12 | |
| do_info_version() | merged | 0.12 | |
| do_info_vnc() | merged | 0.12 | |
| irq_info() | |||
| mem_info() | |||
| pci_info() | |||
| pcmcia_info() | |||
| pic_info() | |||
| qemu_chr_info() | merged | 0.12 | |
| tlb_info() | |||
| usb_host_info() | |||
| usb_info() |
Testing
History
This was the fourth proposal for a Monitor protocol, past discussions can be found in the following links: