From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.bugs Subject: bug#32405: Turning misc objects into pseudovectors Date: Wed, 8 Aug 2018 22:01:09 -0700 Organization: UCLA Computer Science Department Message-ID: <89c3c3be-4c08-32c7-7ecf-8bae1aa78305@cs.ucla.edu> References: <20180809025852.28874-1-eggert@cs.ucla.edu> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1533790813 1647 195.159.176.226 (9 Aug 2018 05:00:13 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Thu, 9 Aug 2018 05:00:13 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 Cc: 32405@debbugs.gnu.org To: Stefan Monnier Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Thu Aug 09 07:00:08 2018 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fnd3P-0000Gb-AG for geb-bug-gnu-emacs@m.gmane.org; Thu, 09 Aug 2018 07:00:07 +0200 Original-Received: from localhost ([::1]:47359 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fnd5U-0004Uk-Cr for geb-bug-gnu-emacs@m.gmane.org; Thu, 09 Aug 2018 01:02:16 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:37516) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fnd5K-0004S6-KC for bug-gnu-emacs@gnu.org; Thu, 09 Aug 2018 01:02:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fnd5H-0008DB-GO for bug-gnu-emacs@gnu.org; Thu, 09 Aug 2018 01:02:06 -0400 Original-Received: from debbugs.gnu.org ([208.118.235.43]:40429) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1fnd5H-0008D5-BD for bug-gnu-emacs@gnu.org; Thu, 09 Aug 2018 01:02:03 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1fnd5H-0005R2-3C for bug-gnu-emacs@gnu.org; Thu, 09 Aug 2018 01:02:03 -0400 X-Loop: help-debbugs@gnu.org In-Reply-To: <20180809025852.28874-1-eggert@cs.ucla.edu> Resent-From: Paul Eggert Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 09 Aug 2018 05:02:03 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 32405 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: patch Original-Received: via spool by 32405-submit@debbugs.gnu.org id=B32405.153379088620828 (code B ref 32405); Thu, 09 Aug 2018 05:02:03 +0000 Original-Received: (at 32405) by debbugs.gnu.org; 9 Aug 2018 05:01:26 +0000 Original-Received: from localhost ([127.0.0.1]:45443 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fnd4g-0005Ps-C7 for submit@debbugs.gnu.org; Thu, 09 Aug 2018 01:01:26 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:36516) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1fnd4c-0005Pb-Jq for 32405@debbugs.gnu.org; Thu, 09 Aug 2018 01:01:24 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 517F71600CC; Wed, 8 Aug 2018 22:01:16 -0700 (PDT) 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 pMRlOQUwi5xO; Wed, 8 Aug 2018 22:01:10 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 7BE9A160516; Wed, 8 Aug 2018 22:01:10 -0700 (PDT) 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 tGDsoof2aWph; Wed, 8 Aug 2018 22:01:10 -0700 (PDT) Original-Received: from [192.168.1.9] (unknown [47.154.30.119]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 394391600CC; Wed, 8 Aug 2018 22:01:10 -0700 (PDT) Openpgp: preference=signencrypt Autocrypt: addr=eggert@cs.ucla.edu; prefer-encrypt=mutual; keydata= xsFNBEyAcmQBEADAAyH2xoTu7ppG5D3a8FMZEon74dCvc4+q1XA2J2tBy2pwaTqfhpxxdGA9 Jj50UJ3PD4bSUEgN8tLZ0san47l5XTAFLi2456ciSl5m8sKaHlGdt9XmAAtmXqeZVIYX/UFS 96fDzf4xhEmm/y7LbYEPQdUdxu47xA5KhTYp5bltF3WYDz1Ygd7gx07Auwp7iw7eNvnoDTAl KAl8KYDZzbDNCQGEbpY3efZIvPdeI+FWQN4W+kghy+P6au6PrIIhYraeua7XDdb2LS1en3Ss mE3QjqfRqI/A2ue8JMwsvXe/WK38Ezs6x74iTaqI3AFH6ilAhDqpMnd/msSESNFt76DiO1ZK QMr9amVPknjfPmJISqdhgB1DlEdw34sROf6V8mZw0xfqT6PKE46LcFefzs0kbg4GORf8vjG2 Sf1tk5eU8MBiyN/bZ03bKNjNYMpODDQQwuP84kYLkX2wBxxMAhBxwbDVZudzxDZJ1C2VXujC OJVxq2kljBM9ETYuUGqd75AW2LXrLw6+MuIsHFAYAgRr7+KcwDgBAfwhPBYX34nSSiHlmLC+ KaHLeCLF5ZI2vKm3HEeCTtlOg7xZEONgwzL+fdKo+D6SoC8RRxJKs8a3sVfI4t6CnrQzvJbB n6gxdgCu5i29J1QCYrCYvql2UyFPAK+do99/1jOXT4m2836j1wARAQABzSBQYXVsIEVnZ2Vy dCA8ZWdnZXJ0QGNzLnVjbGEuZWR1PsLBfgQTAQIAKAUCTIByZAIbAwUJEswDAAYLCQgHAwIG FQgCCQoLBBYCAwECH Content-Language: en-US X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 208.118.235.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:149370 Archived-At: > AFAIK the main issue with pseudovectors is that their allocation is > slower and suffers more from fragmentation (because we don't use > a size-segregated allocation algorithm (like Linux's SLAB, for example) > for them). Pseudovectors do have size-segregated allocation; see the vector_free_lis= ts=20 array. Although it's not as fancy as Linux's SLAB, I hope it's enough for= Emacs;=20 if not we could of course make it fancier. To some extent the point of this change is that we don't need a separate=20 Lisp_Object tag in order to have size-segregated allocation, since pseudo= vectors=20 already do that. > Are you sure the new code is faster overall? That's what I measured with 'make compile-always', yes. Of course this is= just=20 one benchmark. (My original intuition was that nobody would notice the=20 difference....) > There is also a potential issue in terms of the resulting heap size of > markers (which may bump up from 6 words to 8 words, IIRC, unless your > patch does something to keep it down to 6) On a 64-bit platform the heap size of markers does not grow. The old size= is 6=20 words (sizeof (union aligned_Lisp_Misc) is 48), and the new size is also = 6 words=20 (sizeof (struct Lisp_Marker) is also 48).