Dom0 max RAM - Low memory Qubes OS installations

Could you paste (not re-type but paste from dom0), if not whole grub, but at least whole XEN_DEFAULT line
Did you update dom0 recently?
kernel-5.10.109-1.fc32.qubes.x86_64
Did you try to regenerate initramfs?
Maybe you should try kernel-latest. I’m using it for months, without issues.
Did you track journalctl -f while recreating grub?
Did you grep it or dmesg after reboot?
I’m not saying any of these would help, but something you could try until someone else comes up with a better tip.

Hi,

According to the widget on the top right corner of my desktop Dom0 is using around 3200MB all time.
Is this supposed to happen?

Thanks,

- me.

In the default, yes.
Max_mem for dom0 is 4G

So then: if I assigned 8GB of max RAM to Dom0 it would use 8GB?

Because according to that variable name 4GB is the max RAM that Dom0 could use. And for me it uses around 3000MB all time.

I don’t really know how could I lower the max RAM if it’s already using almost 4GB all time. Am I missing something regarding how RAM works in XEN?

Best regards,

- me.

Setting dom0 RAM higher will lower the available RAM for your VMs. Most people don’t want that.

I know, but I was asking that in order to understand how does RAM allocation works. The idea is I (if possible) reduce the amount of RAM allocated to Dom0.

Dom0, as a linux instance, will try to use the most of your RAM to provide cache for the disk. In fact, it doesn’t really need that much RAM to run. If you didn’t install anything manually in dom0, and has not that many VMs running concurrently (less than 10, I assume), it’s safe to reduce the max_mem to 1536M.

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Okey, thanks for the explanation.
Having thta little extra RAM is going to be a great improvement for me. Also, I use i3 as my VM so I suppose that it’s even lighter than running a full DE.

I’m going to reduce it now.

Thanks again. c:

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