On 14/11/2023 09:30, Fiona Ebner wrote: > Am 13.11.23 um 18:09 schrieb Friedrich Weber: >> >> +xref:qm_ballooning[Automatic memory allocation (ballooning)] is not possible >> +when using PCI(e) passthrough. As the PCI device may use DMA (Direct Memory >> +Access), QEMU needs to map the complete guest memory on VM startup. Hence, >> the >> +QEMU process will use at least the (maximum) configured amount of VM memory >> and >> +setting a minimum amount does not have any effect. When using PCI(e) >> +passthrough, it is recommended to set memory and minimum memory to the same >> +amount and keep the balloning device enabled. However, keep in mind that the > > typo: s/balloning/ballooning/
Oops, thanks. > Is there any advantage to keeping the ballooning device enabled? > >> +memory consumption reported in the GUI for the VM may be much lower than the >> +memory consumption of the QEMU process. > > Maybe mention what the reported value is? In my understanding: If the ballooning device is enabled (and a balloon driver present in the guest), the VM memory usage numbers are taken as reported by the balloon driver [1] (I'd say "as seen from within the guest"?). If the ballooning device is disabled, they are inferred from the rss and vsize of the QEMU process [2], so I'd say "as seen from the host". I guess in the end the user has to decide which perspective they care about? I'll try to make this clearer in the v2. [1] https://git.proxmox.com/?p=qemu-server.git;a=blob;f=PVE/QemuServer.pm;h=c465fb6f64ae30dec5112fc4439f9181c2eba4e9;hb=feb51881d#l3013 [2] https://git.proxmox.com/?p=qemu-server.git;a=blob;f=PVE/QemuServer.pm;h=c465fb6f64ae30dec5112fc4439f9181c2eba4e9;hb=feb51881d#l2967 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
