From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Mark H Weaver Newsgroups: gmane.lisp.guile.devel Subject: Re: Extremely high overhead of 'par-map' Date: Fri, 29 Mar 2013 19:18:04 -0400 Message-ID: <87li9594nn.fsf@tines.lan> References: <1355559152.27310.5.camel@Renee-desktop.suse> <87y5d8rclr.fsf@gnu.org> <1364439334.2730.41.camel@Renee-desktop.suse> <874nfwazc3.fsf@tines.lan> <1364524610.2730.48.camel@Renee-desktop.suse> <87d2uiah6h.fsf@tines.lan> <878v56agp1.fsf_-_@tines.lan> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1364599113 18695 80.91.229.3 (29 Mar 2013 23:18:33 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 29 Mar 2013 23:18:33 +0000 (UTC) Cc: guile-devel To: Noah Lavine Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Sat Mar 30 00:19:00 2013 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1ULiZX-0001lr-7L for guile-devel@m.gmane.org; Sat, 30 Mar 2013 00:18:59 +0100 Original-Received: from localhost ([::1]:37529 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULiZ8-0001hT-Ss for guile-devel@m.gmane.org; Fri, 29 Mar 2013 19:18:34 -0400 Original-Received: from eggs.gnu.org ([208.118.235.92]:35707) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULiZ5-0001hO-A6 for guile-devel@gnu.org; Fri, 29 Mar 2013 19:18:32 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ULiZ3-0001jh-Sd for guile-devel@gnu.org; Fri, 29 Mar 2013 19:18:31 -0400 Original-Received: from world.peace.net ([96.39.62.75]:54600) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ULiZ3-0001jE-OK for guile-devel@gnu.org; Fri, 29 Mar 2013 19:18:29 -0400 Original-Received: from turntable.mit.edu ([18.160.0.29] helo=tines.lan) by world.peace.net with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.72) (envelope-from ) id 1ULiYw-0003dM-NZ; Fri, 29 Mar 2013 19:18:23 -0400 In-Reply-To: (Noah Lavine's message of "Fri, 29 Mar 2013 16:27:17 -0400") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 96.39.62.75 X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:16059 Archived-At: Hi Noah, Noah Lavine writes: > Oh, sorry to email twice so soon, but I have an idea for making > par-map usable in more cases: add a keyword argument called > "block-size". Its value should be a positive integer, and the meaning > is to have each thread do block-size iterations. IMO, we should avoid adding anything like this. It would be hard for callers to know what value to pass. I think it should be possible to make 'par-map' act sensibly and efficiently without this kind of help. > I tried to benchmark it, but got a segmentation fault. I think we > have plenty of work to do here. :-) Ouch. Can you please file a bug report with the full details? Regards, Mark