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 TAA11014 for caml-red; Fri, 4 Aug 2000 19:59:50 +0200 (MET DST) Received: from concorde.inria.fr (concorde.inria.fr [192.93.2.39]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id MAA01168 for ; Fri, 4 Aug 2000 12:08:58 +0200 (MET DST) Received: from pauillac.inria.fr (pauillac.inria.fr [128.93.11.35]) by concorde.inria.fr (8.10.0/8.10.0) with ESMTP id e74A8AX17197; Fri, 4 Aug 2000 12:08:10 +0200 (MET DST) Received: (from xleroy@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id MAA01540; Fri, 4 Aug 2000 12:08:10 +0200 (MET DST) Message-ID: <20000804120810.02409@pauillac.inria.fr> Date: Fri, 4 Aug 2000 12:08:10 +0200 From: Xavier Leroy To: dsl@tepkom.ru, Caml mailing list Subject: Re: Different GCs for OCaml References: <4.3.2.7.0.20000719094927.00aaee20@chasm.org> <20000721165947J.wakita@is.titech.ac.jp> <3986D4B8.748DDE07@tepkom.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.89.1 In-Reply-To: <3986D4B8.748DDE07@tepkom.ru>; from Dmitri Lomov on Tue, Aug 01, 2000 at 05:46:32PM +0400 Sender: weis@pauillac.inria.fr > By the way, did anybody succesfully applied a different > GC to OCaml? I haven't heard of it, and that would be a major undertaking. It's like hand surgery: in principle, it is possible to reconnect a hand to a wrist; in practice, there are so many tendons, nerves and vessels to reconnect... > I've tried to add parallelism -- more specifically, to collect > major heap in a separate thread -- but failed to do so: > as usually with parallel programs, I've got lots of bugs that > were just nightmare to track down. GC bugs are also quite a nightmare... > So, after two weeks of trying, I just abandoned this, with hope > to return to this some day. Damien Doligez's PhD thesis was precisely on a concurrent collector in the style of OCaml's collector. (Actually, this is backwards: the concurrent collector was designed first, and the current OCaml incremental GC was derived from it.) The two POPL papers and the dissertation available from http://pauillac.inria.fr/~doligez/caml-guts/ give a good idea of how difficult efficient concurrent collection is. - Xavier Leroy