On 7/3/19 9:36 AM, Markus Armbruster wrote: > Did this fall through the cracks? > > Denis Plotnikov <dplotni...@virtuozzo.com> writes: > >> Right now QMP and HMP monitors read 1 byte at a time from the socket, which >> is very inefficient. With 100+ VMs on the host this easily reasults in >> a lot of unnecessary system calls and CPU usage in the system. > Yes, reading one byte at a time is awful. But QMP is control plane; I > didn't expect it to impact system performance. How are you using QMP? > Just curious, not actually opposed to improving QMP efficiency. 500 VMs on a host, each 30 seconds libvirts executes AFAIR 3-5 commands with default settings. This results in at least some load. It is not very significant, but it is noticeable.
This reduces idle CPU consumption around 1-2% observable via top, which is not that small amount. Den
