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<p class="MsoNormal">Hi Folks,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’d like to get some opinions on the use of pairs of notification messages for simple events. I get that for complex operations on an instance (create, rebuild, etc) a start and end message are useful to help instrument progress and how
long the operations took. However we also use this pattern for things like aggregate creation, which is just a single DB operation – and it strikes me as kind of overkill and probably not all that useful to any external system compared to a a single event
“.create” event after the DB operation.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is a change up for review to add notifications for service groups which is following this pattern (<a href="https://review.openstack.org/#/c/107954/">https://review.openstack.org/#/c/107954/</a>) – the author isn’t doing anything
wrong in that there just following that pattern, but it made me wonder if we shouldn’t have some better guidance on when to use a single notification rather that a .start/.end pair.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does anyone else have thoughts on this , or know of external systems that would break if we restricted .start and .end usage to long-lived instance operations ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Phil<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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