manikyath

this is the assumption i came to so far, and the platfoms where it "works" have just implemented some sort of in-house script to automate the process.

the "question" in the thread is how to make it re-release RAM to the virtual machine automagically, and if that's possible at all on unraid. i know the balloon driver is needed, i know it doesnt work if PCIe devices are passed trough, the behavior you describe is how far i got as well, but after that the RAM doesnt come back to the VM on demand, like it does with for example proxmox.

by that i assume that this previous assumption was correct, then:

no change on the matter, but I also havent chased it any more. for all i know the latest release of unraid has magically resolved the issue. i've figured out (almost a year ago now) that dynamic memory is a bit weird in KVM, and their own documentation sort of implies that it's not supposed to be used this way. and that dynamic memory also doesnt work on a VM with IOMMU features. i'm assuming that the issue is one of the following: - unraid might accidentially set some flags on the IOMMU side that mess with dynamic memory. - other platforms that focus a lot more on the 'VM farm' aspect of things have just put in the R&D of making it work. given the traction this thread is getting, i think it's safe to say "there's half a douzen of us" that have encountered this issue. i've since concluded that it's better to chase my 'it must be in a VM' limitation, than to chase this oddity with dynamic memory.

so far the only solution i've found is to switch to proxmox, which is a really disappointing to say on the unraid forums.

i run a quad-NIC bonded with "802.3ad", and ran into your thread by accident on my way to check if there was already a bug report for this... for me it's the same issue, the button option is stuck on active-backup, when i reboot my unraid box it'll be set to active-backup (and as a result not get a network connection, because the switch is expecting an 802.3ad setup) when i start the array, but if i first go into the settings menu, set it to 802.3ad, click apply, and then start the array.. it works. the button still says active-backup, but it's running 802.3ad.

i've been on quite a search to figure out if i can make a VM in unraid that dynamically gets memory assigned when it needs it, or when the host doesnt need it. Either way will work really. In short, my goal is to consolidate some tasks from another server into a VM on my unraid machine. Because of some long-winded requirements i cant use a docker container, and i dont have enough RAM in my server to dedicate the amount the VM 'could' use, while still having enough memory spare for what other services on my box 'could' use. Having a shared 'pool' is fine however. For solving this problem, i got interested in the ways behind the "Initial Memory" and "Max Memory" settings in the VM settings. However, the behavior doesnt seem to make much sense in my testing. My current setup is a host machine with 32GB RAM, running unraid 6.9.2 The virtual machine is running debian 11.2, configured with 2GB Initial memory and 16GB Max memory. Other services currently running are consuming approximately The behavior i'm experiencing here is as follows: - once the VM starts, it shows to have 16GB memory allocated - as the system has started up, the memory allocation depicted by unraid, and in the VM as listed by htop, lowers down to around the initial memory configruation: 2GB in unraid, and about 1.6GB in debian (i'm assuming driver losses here.) - when i run a memory intensive application in the VM, it'll start eating into swapfile, and eventually crashes with an out of memory error, the VM never gets any additional memory past what it dropped down to after startup. - i can manually assign the VM more memory in the 2 to 16GB memory range trough terminal commands on unraid, but past the initial shrink it doesnt appear to take any automatic action in either direction. Is this how it is intended to work with unraid? Is there supposed to be any sort of automated process that allocates memory as needed, and it just appears broken for my exact setup? i've dug trough every bit of documentation i could find on the topic, and have come up short unfortunately.