On Mon, 12 Jun 2023 03:00:23 GMT, Tom Rodriguez <ne...@openjdk.org> wrote:
>> Doug Simon has updated the pull request with a new target base due to a
>> merge or a rebase. The pull request now contains one commit:
>>
>> copy system properties into libgraal more efficiently
>
> src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/services/Services.java line
> 314:
>
>> 312: String key = toJavaString(unsafe, unsafe.getLong(prop +
>> keyOffset));
>> 313: long valueAddress = unsafe.getLong(prop + valueOffset);
>> 314: if (valueAddress != 0) {
>
> Is the lazy value construction really necessary? It seems like it requires
> quite a bit of extra machinery.
In big apps, I image there can be quite some large system property values (e.g.
`java.class.path`) so we don't want to pay memory overhead per libgraal isolate
for such properties as they're ignored by libgraal.
I realized I can reduce the extra machinery based on the fact that
`SystemProperties` is unmodifiable:
https://github.com/openjdk/jdk/pull/14291/commits/6c346d35923402fb5d6ae0ef83214f8f0ca07b69
The only method that still eager converts the string is
`SystemProperties.values()` but that's fine as it's not used by JVMCI or Graal.
I think the trade off is now acceptable?
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/14291#discussion_r1226352693
