preloading high-value entity metadata

[Cantor, Scott]

> AFAIK, that cache only affects the startup process (like the backing file on
> FileBackedHTTPMetadataProvider).

I don't know what else you're trying to do.

> Please take a look at Example 4 on the ChainingMetadataProvider page.
> [1] That example uses FileBackedHTTPMetadataProvider to short-circuit a
> DynamicHTTPMetadataProvider.

That doesn't really make any sense. If you can use an aggregate, you're done. There's no point in doing both. A File-based metadata source locally might be an alternative to the cache approach, that's always been the usual way of hijacking a remote source because you need to correct for an error or something. That can be a batch file or LocalDynamic, whichever. It's always a good idea to have that hook, but most people already have local metadata installed, and yes, it's usually best if it's first.

> Is that something we want to document, and
> if so, how can it be generalized? (I'm pretty sure the answer to the latter
> question is that it can't be generalized, at least not with what we have available
> to us now.)

It makes no sense to me at all. If you're beta testing a dynamic source or something like that, you'd do the opposite, put the aggregate source after the dynamic lookup as a fallback.

The problem right now is that Dynamic can't run anywhere but the end of a chain because it doesn't cache failure. Until that's cleaned up it has to be used very carefully or it will take down your system performance-wise.

-- Scott