RFR: 8305753: Allow JIT compilation for -Xshare:dump [v2]

[Matias Saavedra Silva]

On Wed, 18 Oct 2023 21:49:21 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> src/hotspot/share/runtime/arguments.cpp line 3048:
>> 
>>> 3046:       // -Xcomp may use excessive CPU for the test tiers. Also, -Xshare:dump runs a small and fixed set of
>>> 3047:       // Java code, so there's not much benefit in running -Xcomp.
>>> 3048:       log_info(cds)("reduced -Xcomp to -Xmixed");
>> 
>> Is it preferable to reduce the user-selected option over throwing an error for incompatible options?
>
> We have many test jobs that add `-Xcomp` to every test case, so throwing an error will cause these tests to fail.
> 
> If we don't reduce the strength to `-Xmixed`, then many of these tests will fail due to timeout, forcing us to change the timeout value in these tests.
> 
> So I think changing to `-Xmixed` is a good compromise to do some testing with the JIT during `-Xshare:dump` without being intrusive.

That makes perfect sense! I am still concerned about the idea taking a user option and reducing it to an option they didn't ask for... I will trust your judgement

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

PR Review Comment: https://git.openjdk.org/jdk/pull/16233#discussion_r1364807525