GET performance querying using SemVerLevel=2.0.0 very poor on NuGet feed

What are strategies for improving performance of GET requests that employ the SemVerLevel=2.0.0 flag?

When comparing the performance of the following request constructions the one using SemVerLevel was orders of magnitude slower that one specifying the same package and a specific version (~20 seconds vs ~20 ms). The number of package versions for the specific package is only in the hundreds, but the feed contains over 100,000 package versions.

~20ms

Id='<package>', Version='<version>'

~20s

?semVerLevel=2.0.0&$filter=tolower(Id)eq'<package>'

Is it possible to create an index to improve performance or are there other strategies?

Product: ProGet
Version: 4.7.13

The problem is not semVerLevel, but tolower(Id).

Can you remove the toLower()?

We have special handling for "Id eq 'package'" queries to make them very fast, but when you put "tolower" on there, it disables that, forcing enumeration of every package version and frontend filtering. This is why it's very slow.

We're using Paket (https://fsprojects.github.io/Paket/) for package resolution and the source code appears to force the tolower(Id), so it won't be that easy to change. Is it possible to similarly support improved performance with "tolower(Id)"?

It makes sense why the performance is poor if it falls back to full enumeration.

As Packet is an "unofficial" and not-Microsoft supported client, we don't test against it. Thus we'd rather not add a pattern predictor/otpimizer to suit their usage, work-around client bugs, etc.

Intead, I would recommend to submit an issue or pull request to their team; in the past they have been responsive to adding things to make Packet work with ProGet users, such as authentication.

I created a ticket with Paket, and they did resolve the issue via an update to their code base. Testing with version 5.6.6 seems to have fixed the issue.

https://github.com/fsprojects/Paket/issues/2466