[Users] Can host hooks be used to implement the following policy to avoid "boot storm"?

[lofyer]

于 2013/5/26 15:41, Itamar Heim 写道:
> On 05/26/2013 09:59 AM, Roy Golan wrote:
>> On 05/24/2013 03:22 PM, Itamar Heim wrote:
>>> On 05/23/2013 04:23 PM, lofyer wrote:
>>>> Can host hooks be used to implement the following policy to avoid 
>>>> "boot
>>>> storm"?
>>>>
>>>> 1.count and sort VMs awaiting for boot.
>>>> 2.If the count is less than or equal to, for example 5, then boot all
>>>> VMs and exit the script.
>>>> 3.Otherwise, boot and dequeue vm0 to vm4, and minus the count by 5.
>>>> 4.Sleep some time, and go to step 2.
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>>>
>>> hooks run one on vm-start one by one. would be a bit tricky to do the
>>> above.
>>> roy - didn't you add some mechanism to throttle boot storms in the
>>> engine?
>> yes at RunVmCommandBase.delay(Guid vdsId) - but it doesn't fit here.
>> It'll delay the VM run only when there is no free memory to run the VM
>> and will wait till engine signals after gathering statistics of
>> powering up VMs.
>
> lofyer - any other issue other than memory bottleneck you were trying 
> to resolve?
>
> Thanks,
> Itamar
I think only cpu_load here. If I start 8 VMs(1G memory each) in a 16G 
host, it will be very slow for VMs to enter the desktop mode from the 
time I click "start".
At first I thought it would be a resolution if I put these boot 
processes into a linear squence or delay a random period by using hooks.
Is there an option that I can choose to arrange the boot squence in the 
engine?
However, since each VM takes quite a long time to startup, there is no 
need to do that. Just plug in more CPUs......