[GHC] #8400: Migrate the RTS to use libuv (or libev, or libevent)

[GHC]

#8400: Migrate the RTS to use libuv (or libev, or libevent)
----------------------------------------------+----------------------------
       Reporter:  schyler                     |             Owner:
           Type:  feature request             |  simonmar
       Priority:  normal                      |            Status:  new
      Component:  Runtime System              |         Milestone:
       Keywords:                              |           Version:
   Architecture:  Unknown/Multiple            |  Operating System:
     Difficulty:  Project (more than a week)  |  Unknown/Multiple
     Blocked By:                              |   Type of failure:
Related Tickets:  635, 7353                   |  None/Unknown
                                              |         Test Case:
                                              |          Blocking:
----------------------------------------------+----------------------------
 This is mainly a reference discussion ticket.

 libuv (https://github.com/joyent/libuv) is a lightweight library which
 allows asynchronous IO across OpenBSD, Linux, Darwin, Windows etc by
 utilizing the fastest implementation on each system (epoll, kqueue, IOCP,
 event ports). These specialized IO polling methods are '''much''' faster
 on their respective platforms than just using select() like the RTS
 currently does.

 Additionally, it also provides cross platform threads, mutex, condition
 vars, terminal input/output and term settings w/ cross platform ANSI
 escape code handling, thread pools, cross platform HRC's etc. It's
 currently significantly faster than libevent and slightly faster than
 libev (and no doubt faster than rolling our own stuff). Because it's
 maintained and utilized heavily by Node.js it's in extremely active and
 maintained development.

 Rewriting a portion of the RTS to utilize libuv would have the following
 benefits;
 * We could ditch basically all of our platform specific code. Everything
 under rts/win32 and rts/posix, except the SEH stuff, could be deleted.
 * libuv is tuned for speed on each platform. This would be an optimization
 to all our async IO stuff.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8400>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler