Re: [PATCH v2 0/8] mm/memory_hotplug: allow to specify a default online_type

From: Vitaly Kuznetsov
Date: Wed Mar 18 2020 - 11:00:31 EST


Baoquan He <bhe@xxxxxxxxxx> writes:

> Is there a reason hyperV need boot with small memory, then enlarge it
> with huge memory? Since it's a real case in hyperV, I guess there must
> be reason, I am just curious.
>

It doesn't really *need* to but this can be utilized in e.g. 'hot
standby' schemes I believe. Also, it may be enough if the administrator
is just trying to e.g. double the size of RAM but the VM is already
under memory pressure. I wouldn't say that these cases are common but
afair bugs like 'I tried adding more memory to my VM and it just OOMed'
were reported in the past.

--
Vitaly