RFR: 8234131: Miscellaneous changes imported from jsr166 CVS 2020-12 [v2]

[Martin Buchholz]

OK, rollback committed to CVS:

--- src/main/java/util/concurrent/ThreadPoolExecutor.java 27 Nov 2020
17:42:00 -0000 1.194
+++ src/main/java/util/concurrent/ThreadPoolExecutor.java 8 Dec 2020
20:31:54 -0000
@@ -1522,13 +1522,11 @@
             // As a heuristic, prestart enough new workers (up to new
             // core size) to handle the current number of tasks in
             // queue, but stop if queue becomes empty while doing so.
-            /*
             int k = Math.min(delta, workQueue.size());
             while (k-- > 0 && addWorker(null, true)) {
                 if (workQueue.isEmpty())
                     break;
             }
-            */
         }
     }

On Tue, Dec 8, 2020 at 4:04 AM Doug Lea <dl at cs.oswego.edu> wrote:

>
> On 12/8/20 3:56 AM, Alan Bateman wrote:
> >> 1558:                     break;
> >> 1559:             }
> >> 1560:             */
> > Is this meant to be commented out?
> Yes, but It should be marked as a possible improvement, not yet
> committed. While this (prestarting) would improve performance in some
> scenarios, it may also disrupt expectations and even tooling in some
> existing usages, which we haven't fully checked out.
>
>