"migrate-set-cache-size" is deprecated since QEMU 2.11.0 and libvirt will stop using it (see bug 1845012). We can remove the QMP command once libvirt stops using it.
(In reply to Li Xiaohui from comment #0) > Description of problem: > "migrate-set-cache-size" is deprecated since qemu-4.2 from qemu.org [1] and > should be replaced by 'migrate-set-parameters'. > https://wiki.qemu.org/ChangeLog/4.2#Migration Now I noticed this BZ is assigned to the qemu-kvm component. Can you clarify what's the purpose of this BZ? Where exactly the command still needs to be replaced?
(In reply to Eduardo Habkost from comment #5) > (In reply to Li Xiaohui from comment #0) > > Description of problem: > > "migrate-set-cache-size" is deprecated since qemu-4.2 from qemu.org [1] and > > should be replaced by 'migrate-set-parameters'. > > https://wiki.qemu.org/ChangeLog/4.2#Migration > > Now I noticed this BZ is assigned to the qemu-kvm component. Can you > clarify what's the purpose of this BZ? Now migrate-set-cache-size command still can be used in qemu-kvm-5.0, but libvirt have removed it from v4.3.0+. I think we need do corresponding action to remove it from qemu side, so file this bz. > Where exactly the command still needs to be replaced? it should be replaced by "migrate_set_parameter xbzrle-cache-size xx"
migrate-set-cache-size (and the corresponding query command) could still be used by the dedicated libvirt APIs. When the cache size is passed as a parameter to the migration API, libvirt will use xbzrle-cache-size instead. However, there are patches on review upstream which replace several deprecated QMP commands with the corresponding parameters for migrate-set-parameters and query-migrate-parameters: https://www.redhat.com/archives/libvir-list/2020-June/msg00444.html We also have several BZs that track these changes in libvirt: https://bugzilla.redhat.com/show_bug.cgi?id=1829543 https://bugzilla.redhat.com/show_bug.cgi?id=1829544 https://bugzilla.redhat.com/show_bug.cgi?id=1829545 https://bugzilla.redhat.com/show_bug.cgi?id=1845012
(In reply to Li Xiaohui from comment #6) > > Now I noticed this BZ is assigned to the qemu-kvm component. Can you > > clarify what's the purpose of this BZ? > Now migrate-set-cache-size command still can be used in qemu-kvm-5.0, but > libvirt have removed it from v4.3.0+. > I think we need do corresponding action to remove it from qemu side, so file > this bz. Thanks. I will update the bug summary and description to indicate that the goal is to remove the QMP command from QEMU, but this is very low priority.