https://bugzilla.redhat.com/show_bug.cgi?id=1161617
Add command to allow adding and removing IOThreads from the domain including
the configuration and live domain.
$ virsh iothreadadd --help
NAME
iothreadadd - add an IOThread to the guest domain
SYNOPSIS
iothreadadd <domain> <id> [--config] [--live] [--current]
DESCRIPTION
Add an IOThread to the guest domain.
OPTIONS
[--domain] <string> domain name, id or uuid
[--id] <number> iothread for the new IOThread
--config affect next boot
--live affect running domain
--current affect current domain
$ virsh iothreaddel --help
NAME
iothreaddel - delete an IOThread from the guest domain
SYNOPSIS
iothreaddel <domain> <id> [--config] [--live] [--current]
DESCRIPTION
Delete an IOThread from the guest domain.
OPTIONS
[--domain] <string> domain name, id or uuid
[--id] <number> iothread_id for the IOThread to delete
--config affect next boot
--live affect running domain
--current affect current domain
Assuming a running $dom with multiple IOThreads assigned and that
that the $dom has disks assigned to IOThread 1 and IOThread 2:
$ virsh iothreadinfo $dom
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
3 0-1
$ virsh iothreadadd $dom 1
error: invalid argument: an IOThread is already using iothread_id '1' in iothreadpids
$ virsh iothreadadd $dom 1 --config
error: invalid argument: an IOThread is already using iothread_id '1' in persistent iothreadids
$ virsh iothreadadd $dom 4
$ virsh iothreadinfo $dom
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
3 0-1
4 0-3
$ virsh iothreadinfo $dom --config
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
3 0-1
$ virsh iothreadadd $dom 4 --config
$ virsh iothreadinfo $dom --config
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
3 0-1
4 0-3
Assuming the same original configuration
$ virsh iothreaddel $dom 1
error: invalid argument: cannot remove IOThread 1 since it is being used by disk 'vde'
$ virsh iothreaddel $dom 3
$ virsh iothreadinfo $dom
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
$ virsh iothreadinfo $dom --config
IOThread ID CPU Affinity
---------------------------------------------------
1 2
2 3
3 0-1
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