1. 11 Nov, 1999 1 commit
  2. 09 Nov, 1999 1 commit
    • simonmar's avatar
      [project @ 1999-11-09 15:46:49 by simonmar] · 30681e79
      simonmar authored
      A slew of SMP-related changes.
      
       - New locking scheme for thunks: we now check whether the thunk
         being entered is in our private allocation area, and if so
         we don't lock it.  Well, that's the upshot.  In practice it's
         a lot more fiddly than that.
      
       - I/O blocking is handled a bit more sanely now (but still not
         properly, methinks)
      
       - deadlock detection is back
      
       - remove old pre-SMP scheduler code
      
       - revamp the timing code.  We actually get reasonable-looking
         timing info for SMP programs now.
      
       - fix a bug in the garbage collector to do with IND_OLDGENs appearing
         on the mutable list of the old generation.
      
       - move BDescr() function from rts/BlockAlloc.h to includes/Block.h.
      
       - move struct generation and struct step into includes/StgStorage.h (sigh)
      
       - add UPD_IND_NOLOCK for updating with an indirection where locking
         the black hole is not required.
      30681e79
  3. 02 Nov, 1999 1 commit
    • simonmar's avatar
      [project @ 1999-11-02 15:05:38 by simonmar] · f6692611
      simonmar authored
      This commit adds in the current state of our SMP support.  Notably,
      this allows the new way 's' to be built, providing support for running
      multiple Haskell threads simultaneously on top of any pthreads
      implementation, the idea being to take advantage of commodity SMP
      boxes.
      
      Don't expect to get much of a speedup yet; due to the excessive
      locking required to synchronise access to mutable heap objects, you'll
      see a slowdown in most cases, even on a UP machine.  The best I've
      seen is a 1.6-1.7 speedup on an example that did no locking (two
      optimised nfibs in parallel).
      
      	- new RTS -N flag specifies how many pthreads to start.
      
      	- new driver -smp flag, tells the driver to use way 's'.
      
      	- new compiler -fsmp option (not for user comsumption)
      	  tells the compiler not to generate direct jumps to
      	  thunk entry code.
      
      	- largely rewritten scheduler
      
      	- _ccall_GC is now done by handing back a "token" to the
      	  RTS before executing the ccall; it should now be possible
      	  to execute blocking ccalls in the current thread while
      	  allowing the RTS to continue running Haskell threads as
      	  normal.
      
      	- you can only call thread-safe C libraries from a way 's'
      	  build, of course.
      
      Pthread support is still incomplete, and weird things (including
      deadlocks) are likely to happen.
      f6692611
  4. 19 Oct, 1999 1 commit
  5. 10 Sep, 1999 1 commit
  6. 25 Aug, 1999 1 commit
    • simonmar's avatar
      [project @ 1999-08-25 16:11:43 by simonmar] · c6ab4bfa
      simonmar authored
      Support for thread{WaitRead,WaitWrite,Delay}.  These should behave
      identically to the 3.02 implementations.
      
      We now have the virtual timer on during all program runs, which ticks
      at 50Hz by default.  This is used to implement threadDelay, so you
      won't get any better granularity than the tick frequency
      unfortunately.  It remains to be seen whether using the virtual timer
      will have a measurable impact on performance for non-threadDelaying
      programs.
      
      All operations in the I/O subsystem should now be non-blocking with
      respect to other running Haskell threads.  It remains to be seen
      whether this will have a measurable performance impact on
      non-concurrent programs (probably not).
      c6ab4bfa
  7. 16 Mar, 1999 1 commit
    • simonm's avatar
      [project @ 1999-03-16 13:20:07 by simonm] · 456eca73
      simonm authored
      Improvements to the threading model.
      
         - asynchronous exceptions supported.
      
      	- killThread# can now raise an exception in the specified
      	  thread.  It's new type is
      
      		killThread# :: ThreadId# -> Exception -> IO ()
      
      	  High-level versions:
      
      		killThread :: ThreadId -> IO ()
      		raiseInThread :: ThreadId -> Exception -> IO ()
      
      	  (killThread raises a 'ThreadKilled' exception in the
      	   specified thread).
      
      	  If the thread has no exception handler, it is killed
      	  as before.  Otherwise, the exception is passed to
      	  the innermost CATCH_FRAME and the thread is woken up
      	  if it was blocked.  The current computation is
      	  suspended, instead of being replaced by the exception
      	  (as is the case with throw).
      
      	  Sending an exception to the current thread works too.
      
         - new primitive: myThreadId# :: IO ThreadId# and corresponding
           high-level version myThreadId :: IO ThreadId.
      
         - new primitive: yield# :: IO (), and yield :: IO ().
      
         - the TSO now contains a pointer to the resource currently blocked
           on (MVAR or BLACKHOLE_BQ).
      
        - Add a giant comment to TSO.h about what the various link fields
          are supposed to do, and invariants etc.
      456eca73
  8. 02 Mar, 1999 1 commit
  9. 05 Feb, 1999 1 commit
  10. 02 Dec, 1998 1 commit