Hi Alan, I ran my example on JDK 21 because it uses Thread.sleep. In an earlier message on the mailing list I learned that virtual‑thread performance on JDK 25 was worse for this kind of scenario compared with JDK 21, and that the issue is supposed to be fixed in JDK 25.0.3 — which has not been released yet.
That said, this does not affect the main point of my message: I’m asking for advice about using pooled virtual threads to work around third‑party libraries that implement buffer pools via ThreadLocal. Thank you, Jianbin Chen Alan Bateman <[email protected]> 于2026年1月24日周六 16:34写道： > > > On 24/01/2026 05:55, Jianbin Chen wrote: > > : > > > > I constructed the Executor directly with > > Executors.newVirtualThreadPerTaskExecutor(); > > however, the run results still show that the pooled virtual‑thread > > behavior outperforms the non‑pooled virtual threads. > > This looks like it is benchmarking Thread.sleep so a different topic to > that of libraries that are caching objects in thread locals. > > For the Thread.sleep test then it would easier to discuss if converted > to a JMH benchmark as there are warmup issues in the test you included. > Also just to note that the Thread.sleep implementation has changed > significantly changed since JDK 21 so you will see very different > results with JDK 25 runs (some of the messages in the discussion speak > of JDK 21, the subject line in the mails say "JDK 25", so I'm guessing > you might be testing both). > > -Alan >
