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Re: A single cross-zone database?
On Mar 16, 2011, at 12:23 PM, Paul Voccio wrote:
> Not only is this expensive, but there is no way I can see at the moment to do pagination, which is what makes this really expensive. If someone asked for an entire list of all their instances and it was > 10,000 then I would think they're ok with waiting while that response is gathered and returned. However, since the API spec says we should be able to do pagination, this is where asking each zone for all its children every time gets untenable.
This gets us into the caching issues that were discussed at the last summit. We could run the query and then cache the results at the endpoint, but this would require accepting some level of staleness of the results. The cache would handle the paging, and some sort of TTL would have to be established as a balance between performance and staleness.
-- Ed Leafe