On Fri, 18 Dec 2020 20:11:26 GMT, Stuart Marks <sma...@openjdk.org> wrote:
> I have to say that introducing a ThreadLocal here seems like a step in the > wrong direction. With a ThreadLocal, if I read this correctly, a > MessageDigest will be cached with each thread that ever calls this API, and > it won't be garbage collected until the thread dies. Some threads live > indefinitely, e.g., the ones in the fork-join common pool. Is this what we > want? Is UUID creation so frequent that each thread needs its own, or could > thread safety be handled using a simple locking protocol? This is a good point. Significant effort has gone into recent releases to reduce the use of TLs in the (JDK-8245309, JDK-8245308, JDK-8245304, JDK-8245302) so adding new usages is a disappointing. So I think this PR does need good justifications, and probably a lot more exploration of options. ------------- PR: https://git.openjdk.java.net/jdk/pull/1821
