Hi,<br><br><div class="gmail_quote">On Thu, Oct 27, 2011 at 8:45 AM, Ryan Newton <span dir="ltr">&lt;<a href="mailto:rrnewton@gmail.com">rrnewton@gmail.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">

Based a quick perusal of Hackage there does not seem to be a lot of work in this area.  Of course, for Haskell the importance of this topic may be diminished relative to pure data structures, but for doing systems-level work like monad par good concurrent data structures are also very important.

</blockquote><div><br>Gregory Collins and I haven&#39;t wanted a fast lock-free hashtable for some time. There&#39;s also a priority queue (inside an IORef) in the I/O manager that could use a replacement. Note that this priority queue needs to support access both by priority and key.<br>

 </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div>We are about to embark on some work to fix this problem for monad-par &amp; Deques, but if there are others working in this vicinity it would be nice to team up.  </div>

<div>   We are going to try both pure Haskell approaches using the new casMutVar# primop as well as wrapping foreign data structures such as those provided by TBB.  There are a whole bunch of issues with the latter -- see Appendix A and help me out if you know how to do this.</div>

</blockquote><div><br>You could try the FFI approach if it&#39;s not too much work but I expect it to perform worse than a native Haskell version. It&#39;d also be bad for the GC, which doesn&#39;t like having lots of small pinned objects as they fragment the heap. I&#39;d rather look into what primops/compiler optimizations we&#39;re lacking to be able to do this well from within Haskell.<br>

<br>-- Johan<br><br></div></div>