Build performance issue of swift-testing

[Kyle-Ye]

Description

Before migrating to use "swift-testing", one of my package's average CI time is as the following

XCTest	macOS 13 + Swift 5.9.2	Ubuntu + Swift 5.9.2
Swift Test(Debug+Covage)	45s	20s
Swift Test(Release)	34s	27s

Most the job will do its job less in 1 min.

However after fully migrate all my test case to swift-testing, the CI time exploded especially with Release configuration.

Expected behavior

It is expected the build time will increase due to the usage of swift macro. And 2~3 min looks normal and acceptable.

Increased to more than 10 min is definitely means something is wrong here IMO.

And my question is the following:

1. Is this a known issue?
2. Is this expected for Swift 5.9 (or 5.10) client only and the issue will not happen for Swift Snapshots toolchain?
3. Is there a workaround for this currently?

Actual behavior

Testing	macOS 13 + Swift 5.9.2	Ubuntu + Swift 5.9.2
Swift Test(Debug+Covage)	4min3s	3min24s
Swift Test(Release)	11min19s	12min37s

Steps to reproduce

No response

swift-testing version/commit hash

swift-testing 0.2

Swift & OS version (output of swift --version ; uname -a)

Swift 5.9.2