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A question about this bug:<br>
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<a href="https://bugs.launchpad.net/ceilometer/+bug/1061817">https://bugs.launchpad.net/ceilometer/+bug/1061817</a><br>
<br>
In the billing program we are currently writing we've partly
accounted for resetting of values in a given period for the
cumulative metrics, but since we need high accuracy especially for
metrics like network.incoming/outgoing, we are likely to lose
chargeable data if someone resets a VM, or a VM goes down.<br>
<br>
example: <br>
10min pipeline interval, a reset/shutdown happens 7 mins after the
last poll. The data for those 7 mins is gone. Even terminating a VM
will mean we lose the data in that last interval.<br>
<br>
Fixing the bug so resets don't happen is likely a lot of work, and I
have a feeling will require work in Nova, and probably won't account
for the terminate case.<br>
<br>
On the other hand, would it be possible to setup a notification
based metric that updates cumulative metrics, or triggers a poll
right before the reset/shutdown/suspension/terminate, so we have an
entry right before it resets and don't lose any data? This would
pretty much solve the issue, and as long as it is documented that
the cumulative metrics reset, this would solve most problems.<br>
<br>
Since the 'process_notification' function only gets passed a
'message', I don't know if there is a way to pull the needed data
out from nova using only what is in the message though. <br>
<br>
Any thoughts, or suggestions as to where to start experimenting?<br>
<br>
-Adrian Turjak<br>
<br>
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