FormFeature allocates when unused

[benaadams]

Resolved by: #675

[muratg]

Investigation

[pakrym]

We don't see difference in performance even when removing FormFeature and CookieFeature allocations completely (72d30a5).

[davidfowl]

You mean throughput. We should be looking at memory as well which this does improve right?

[pakrym]

@davidfowl it does, a bit, question is is 88 bytes worth it? And most real world applications use both cookies and forms.

[davidfowl]

Every byte counts. If it's easy and non-breaking lets do it. If it complicates things too much then naw.

[Tratcher]

So far the solutions have been pretty complicated.

[benaadams]

most real world applications use both cookies and forms.

But not most requests > 50% of webpages (8M sample) have a form and they will be served by a GET request without a form data; as well as all the assets on page (images, fonts, script etc)

A lot of requests and sites are unauthenticated don't have cookies (asset servers) and/or don't care about the cookies (3rd party analytic cookie). There's also vogue not to use cookies but to use local storage and tokens for auth and webapi often doesn't use cookies.

(Edit: is response cookies which are used even less, if already set)

So having the features created for every unauthed GET request seems unnecessarily.

question is is 88 bytes worth it?

It is when you start densely packing sites on a server with more restricted RAM so the GC becomes more aggressive. You can create the processes in Jobs to simulate this.

[Yves57]

Just a question for curiosity: why Factories are not a solution (at least for the less used features)?
I imagine something like public void Set<TFeature>(Func<TFeature> factory) in IFeatureCollection, that would allow create the feature only the first time it is requested...

[pakrym]

@Yves57 that's exactly what I've tried: #691

[benaadams]

@Yves57 its carrying the initalization state for the feature that's problematic

[muratg]

This doesn't seem to be bringing a lot of perf benefits.