Hi Didi, I increased the RAM from 16 to 32 and change is instant on the VM, but as you have mentioned, it does not get written right away to VM image. Upon reboot its back to 16GB RAM. At this moment, change is applied, and I am waiting up to 60min to see if the changes will be written to survive reboot. Regarding how to change it, the UI Edit seem to be the way. If I go with /var/run/… file changes fast, even with VM being shutdown. @oVirt does anyone know how long it usually takes to have the change written to VM image? ----- kind regards/met vriendelijke groeten Marko Vrgotic Sr. System Engineer @ System Administration ActiveVideo o: +31 (35) 6774131 m: +31 (65) 5734174 e: m.vrgotic@activevideo.com<mailto:m.vrgotic@activevideo.com> w: www.activevideo.com<http://www.activevideo.com> ActiveVideo Networks BV. Mediacentrum 3745 Joop van den Endeplein 1.1217 WJ Hilversum, The Netherlands. The information contained in this message may be legally privileged and confidential. It is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and/or ActiveVideo Networks, LLC by telephone at +1 408.931.9200 and delete or destroy any copy of this message. From: Yedidyah Bar David <didi(a)redhat.com&gt; Date: Monday, 22 February 2021 at 11:05 To: Vrgotic, Marko <M.Vrgotic(a)activevideo.com&gt; Cc: users(a)ovirt.org <users(a)ovirt.org&gt; Subject: Re: [ovirt-users] oVirt Engine increase RAM and CPU ***CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender!!!*** On Mon, Feb 22, 2021 at 11:01 AM Vrgotic, Marko <M.Vrgotic(a)activevideo.com&gt; wrote: Please note that I do not have any experience with this whatsoever. Also for the further replies below. Just guessing. I suggest to try first on a test system if it's about a production/critical system. I guess that it will mark the VM as requiring a reboot for changes to take effect, and that they'll actually be applied only on hard-reboot (meaning, not just running 'reboot' from inside). So yes, I guess the process should be: 1. Edit as needed 2. Perhaps wait a bit or something like that to make sure changes reached OVF_STORE on the shared storage. No idea how. Perhaps we log enough about this to existing logs, or perhaps you can dump the conf to verify manually. 2. Set global maint, shutdown, clear global maint (and either immediately start the vm or let ha-agent do this for you). I have no idea other than the bugs I was personally involved with (which you can find in bugzilla). Perhaps RHV or oVirt docs have some guidelines, didn't check. If not, then I suppose the guidelines are "Use the defaults and follow recommendations", which mean: 1. Allocate 16GB RAM for the HE VM. Perhaps we even recommend more than that for larger setups, not sure. 2. engine-setup then sets both min and max to 4GB (=25% of RAM). If you do want to play with this, you should of course test thoroughly and carefully :-). Consider also other processes on the machine needing rather-large amounts of memory, including DWH and PostgreSQL (which we also automatically configure and which you can further refine if needed, and also set up to run on separate machines). That's a question for the JVM, not for oVirt :-). I suppose it will simply use a constant size. It should be, if you make sure other stuff (dwh+pg) do not use too much, or you have also enough swap (but then do not expect good performance if you actually run into actually using it). -- Didi