RFR: 6734346: harness reads too many files

[Aleksey Shipilev]

On Mon, 19 Sep 2022 12:12:31 GMT, Daniel Jeliński <djelinski at openjdk.org> wrote:

> This patch fixes a long-standing issue where jtreg reads every java file under a test root (like test/jdk) when generating reports for jobs running a subset of tests.
> On a Windows machine, this reduces the time required to run a single (fast) test and generate report from 15-20 seconds to 1-3 seconds.
> 
> Verified that the generated report looks correct; the report only contains tests that were actually run, so the extra work in scanning every java file was unnecessary.
> 
> Did not verify if the existing tests still pass; I'm new to ant, and couldn't get it to run the tests. Are there any instructions I could use?

For large suites, I work around the similar trouble with `JTREG="OPTIONS=-report:executed"` -- maybe we should (additionally?) change the default for `-report`?

-------------

PR: https://git.openjdk.org/jtharness/pull/38