Re: [RFC] KVM-Autotest: basic parallel test execution

[Avi Kivity <avi@redhat.com>]

Mike Burns wrote:
> Avi Kivity wrote:
>   
>> Michael Goldish wrote:
>>     
>>> Drawbacks:
>>> - requires some initial work to be done by the user -- the user has
>>> to define exactly where each test should run
>>>   
>>>       
>> For me, this is a major drawback.  I'd really like a fire-and-forget
>> solution.  If I have to spend my own time getting this to work, vs.
>> waiting longer for the tests to run on their own, I'll just be lazy.
>>     
> It seems like this is adding another layer of user interaction without
> really getting that much additional functionality.  An administrator of
> kvm-autotest is going to know enough to be able to create control and
> kvm_tests.cfg files that can mimic this already and then just create 2
> jobs in the server to run on different hosts. 
>   

I'm an administrator of kvm-autotest and I have no idea how to create 
control and kvm_tests.cfg files.

Also, I'm a lot more interested in spreading the load on my one host 
rather than on fictional other hosts.  And for that we need a scheduler, 
since different tests need differing amounts of memory and cores.

>>> - test sets need to be modified when tests or hosts are
>>> added/removed, to include/exclude them
>>>   
>>>       
>> This is also annoying -- and likely to stop me from updating.
>>     
> Host definitions already happen on the server and it seems like it would
> be confusing to have to make sure that the host you choose when setting
> up a test is setup correctly in your config files. 
>   

Host setups should be separated from test setup, so that tests can be 
continuously updated while the host setup is kept static.

>> I'd really like this to be automated, just specify a set of machines
>> and have the jobs distributed.  Furthermore, it is very important to
>> utilize the existing hosts better.  A 4-core 4GB server can easily run
>> a 2x smp 1GB guest and 2 other uniprocessor 1GB guests.  It's wasteful
>> to add more servers when the existing servers are underutilized.
>>
>>     
> Overall, the way I envisioned parallel test execution was having
> multiple tests running on a single machine.  It seems that the server
> already provides most (if not all) the functionality needed to spread
> tests across multiple machines.  I really think this is putting too much
> on the user for very small gains in functionality. 
>   

As a user, I disagree.  I can't calculate what resources are needed by 
each test and make sure they all fit on my host.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.