On Mon, Oct 16, 2023 at 13:36:42 +0000, Chun Feng Wu wrote: > Does this libvirt throttling support “chained throttle filters” for single disk described in QEMU doc: https://github.com/qemu/qemu/blob/master/docs/throttle.txt (“The 'throttle' block filter”) No, libvirt currently still uses the older approach by using 'block_set_io_throttle' QMP command. This was used at the beginning because the 'throttle' layer was not yet ready at the point when libvirt adopted -blockdev. It is sufficient for the throttling options that are currently configurable via libvirt's XML. Note that to use the full potential of the throttle groups and hierarchical throttling will require significant re-engineering of the XML configuration of throttling.