From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: Bug#38708: eq vs eql in byte-compiled code Date: Thu, 2 Jan 2020 15:12:20 -0800 Organization: UCLA Computer Science Department Message-ID: <63be4261-6a6d-bff4-fe0d-a90ecfadb29e@cs.ucla.edu> References: <8cd1b5b2-b94e-ce64-0d70-c1b8b012d685@cs.ucla.edu> <1e0940ff-e418-bafc-66d3-72b562b2c65b@cs.ucla.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="126093"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1 Cc: =?UTF-8?Q?Mattias_Engdeg=c3=a5rd?= , Stefan Monnier , emacs-devel@gnu.org To: Pip Cet Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Jan 03 00:12:45 2020 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1in9dy-000Wf4-2L for ged-emacs-devel@m.gmane.org; Fri, 03 Jan 2020 00:12:42 +0100 Original-Received: from localhost ([::1]:46566 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1in9dw-0008BX-QN for ged-emacs-devel@m.gmane.org; Thu, 02 Jan 2020 18:12:40 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:34229) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1in9dn-00086g-7d for emacs-devel@gnu.org; Thu, 02 Jan 2020 18:12:33 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1in9dl-0001UV-07 for emacs-devel@gnu.org; Thu, 02 Jan 2020 18:12:30 -0500 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:58180) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1in9di-0001Of-UF for emacs-devel@gnu.org; Thu, 02 Jan 2020 18:12:28 -0500 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 0FC0E16005D; Thu, 2 Jan 2020 15:12:22 -0800 (PST) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id XIMM7_8gT3bX; Thu, 2 Jan 2020 15:12:21 -0800 (PST) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 54BD0160061; Thu, 2 Jan 2020 15:12:21 -0800 (PST) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id UN5Xj3SpK6Eg; Thu, 2 Jan 2020 15:12:21 -0800 (PST) Original-Received: from Penguin.CS.UCLA.EDU (Penguin.CS.UCLA.EDU [131.179.64.200]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 389DC16005D; Thu, 2 Jan 2020 15:12:21 -0800 (PST) In-Reply-To: Content-Language: en-US X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:243878 Archived-At: On 1/2/20 4:27 AM, Pip Cet wrote: > For what it's worth, I'm not seeing that effect, and it seems too > large to me to be easily explicable. I'm also puzzled. I reproduced the effect on two smallish hosts (Fedora 31, Ubuntu 18.04.3) running sequentially, but not on a larger one when running with 'make -j14' (RHEL 7.7). I'll look into it a bit more. Could be a cache-size issue. > I might be mistaken, but our hash tables never shrink, do they? That > sounds like a potential problem to me, particularly for people who > mess about with gc settings; but I haven't been able to produce a > problem in practice with your patch. You're right they don't shrink. However, on today's machines I expect that the only problem would be that a hash table too large for its number of entries would not cache as well. >> * Should we try hash-consing floats too? Maybe it wouldn't be as slow as we >> thought, for typical computations anyway.... > > I think the answer is yes here... > >> * The attached patch could probably be sped up a bit by supporting sets as well >> as mappings at the low level, since bignum_map is really just a set of bignums. >> Not sure it's worth the effort, though. > > if it's also yes here. More things for me to look into, I suppose...