Re: [libvirt] [PATCH] docs: correct setmem text plus expand setmaxmem text
2011/1/26 Justin Clift <jclift(a)redhat.com>:
On 20/01/2011, at 11:30 PM, Matthias Bolte wrote:
> 2011/1/19 Justin Clift <jclift(a)redhat.com>:
>> This completes the man page updates required for BZ # 622534:
>>
>> https://bugzilla.redhat.com/show_bug.cgi?id=622534
>
>> -Change the maximum memory allocation limit in the guest domain. This should
>> -not change the current memory use. The memory limit is specified in
>> -kilobytes.
>> +Change the maximum memory allocation limit for an active guest domain.
>> +
>> +Some hypervisors require a larger granularity than kilobytes, and requests
>> +that are not an even multiple will either be rounded down or rejected. For
>> +example, vSphere/ESX rejects the parameter unless the kB argument is evenly
>> +divisible by 1024 (that is, the kB argument happens to represent megabytes).
>
> Actually vSphere/ESX truncates in this case. It rejects in other cases
> (virsh define).
>
> As Dan suggested, I might change this to round up.
With vSphere/ESX, does the virsh "setmaxmem" command work on running guest
domains, or only inactive ones, or ?
I'd *really* like to update the man page docs around this in the next few days, and
I'm still not sure what this command is actually doing in the real world. Heh. ;(
setmaxmem works on inactive guest only.
Thanks for making me test this again, because I found a bug in the ESX
driver, actually in the vSphere API. The API call allows to set max
memory to values that aren't a multiple of 4 megabyte. But such a
virtual machine fails to start as ESX reports a general config fault
for it. The vSphere Client only allows to change this value in 4 mb
steps.
I'll have to fix that.
Matthias