From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from weis@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id JAA22938 for caml-red; Mon, 13 Nov 2000 09:09:44 +0100 (MET) Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id BAA18966 for ; Mon, 13 Nov 2000 01:19:27 +0100 (MET) Received: from mail.is.titech.ac.jp (mail.is.titech.ac.jp [131.112.51.131]) by nez-perce.inria.fr (8.11.1/8.10.0) with SMTP id eAD0JPf22819 for ; Mon, 13 Nov 2000 01:19:25 +0100 (MET) Received: (qmail 9199 invoked from network); 13 Nov 2000 00:19:24 -0000 Received: from dmznat-9.is.titech.ac.jp (HELO localhost) (131.112.51.189) by mail.is.titech.ac.jp with SMTP; 13 Nov 2000 00:19:24 -0000 To: skaller@ozemail.com.au Cc: caml-list@inria.fr Subject: Re: practical functional programming In-Reply-To: <3A0EF904.C65AC976@ozemail.com.au> References: <3A0D5877.5276798B@ozemail.com.au> <3A0E987B.F67FECA5@is.titech.ac.jp> <3A0EF904.C65AC976@ozemail.com.au> X-Mailer: Mew version 1.94.1 on Emacs 20.5 / Mule 4.1 (AOI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <20001113091938O.wakita@is.titech.ac.jp> Date: Mon, 13 Nov 2000 09:19:38 +0900 From: Ken Wakita X-Dispatcher: imput version 990905(IM130) Sender: weis@pauillac.inria.fr In message (<3A0EF904.C65AC976@ozemail.com.au>) from John Max Skaller , talking about "Re: practical functional programming", on Mon, 13 Nov 2000 07:09:40 +1100 skaller> Ken Wakita wrote: skaller> > skaller> > A circumstance where reference counting outperforms modern trace-based skaller> > collectors is where memory access cost is much higher than the skaller> > conventional memory system and thus memory access required for tracing skaller> > is much higher than the cost for counter maintenance. One such example skaller> > is distributed environment. Another maybe systems with very, very slow skaller> > memory such as file systems, persistent object systems, and PDAs. I am skaller> > curious if there are other circumstances using conventional memory skaller> > system where reference counting is faster. skaller> skaller> I don't know how a trace-based collector works. Can you explain? skaller> [Does this have something to do with a write barrier on pointer skaller> stores?] Trace-based collector (or tracing collector) is a name given to a class of garbage collection algorithms that trace the object graph in the heap. It covers most of the garbage collection algorithms, mark&sweep and copying. If you incorporate generational techniques probably you need to use write barrier. Ken Wakita Tokyo Institute of Technology