Open Stack

Hmm. . it was definitely different xen virtual machines on either the
same hypervisor or one that was adjacent to it in an L2 sense. On a
similar environment I have set up now, I notice that the ping time
from one vm to another on the same hypervisor is not noticeably less
than the ping time to a vm on a different hypervisor. Not sure why that
is the case! In any case it is trivial. . ~3 ms for first ping, ~0.3 ms
for subsequent pings. 

"Sandy Walsh" <sandy.walsh at rackspace.com> said:

> Was the db on a separate server or loopback?
> 
> On 03/23/2012 05:26 PM, Mark Washenberger wrote:
>>
>>
>> "Johannes Erdfelt" <johannes at erdfelt.com> said:
>>
>>>
>>> MySQL isn't exactly slow and Nova doesn't have particularly large
>>> tables. It looks like the slowness is coming from the network and how
>>> many queries are being made.
>>>
>>> Avoiding joins would mean even more queries, which looks like it would
>>> slow it down even further.
>>>
>>
>> This is exactly what I saw in my profiling. More complex queries did
>> still seem to take longer than less complex ones, but it was a second
>> order effect compared to the overall volume of queries.
>>
>> I'm not sure that network was the culprit though, since my ping
>> roundtrip time was small relative to the wall time I measured for each
>> nova.db.api call.
>>
>>
>> _______________________________________________
>> Mailing list: https://launchpad.net/~openstack
>> Post to     : openstack at lists.launchpad.net
>> Unsubscribe : https://launchpad.net/~openstack
>> More help   : https://help.launchpad.net/ListHelp
> 
> _______________________________________________
> Mailing list: https://launchpad.net/~openstack
> Post to     : openstack at lists.launchpad.net
> Unsubscribe : https://launchpad.net/~openstack
> More help   : https://help.launchpad.net/ListHelp
>