https://issues.dlang.org/show_bug.cgi?id=13444

          Issue ID: 13444
           Summary: std.concurrency.Mailbox should use a ring buffer
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: performance
          Severity: enhancement
          Priority: P1
         Component: Phobos
          Assignee: sean@invisibleduck.org
          Reporter: andrea.9940@gmail.com

The current Mailbox implementation in std.concurency uses a private List struct where every call to .put() needs to allocate a new node from the GC. A better alternative is a ring buffer which can do all the things the Mailbox needs and faster in every way. The growing time can be compensated by a right call to setMaxMailboxSize() and any random removal can be a swap of the last element with the one being removed.

Forum link: http://forum.dlang.org/thread/fdmopylovwbozsclgacq@forum.dlang.org

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