From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: =?UTF-8?Q?Cl=c3=a9ment_Pit-Claudel?= Newsgroups: gmane.emacs.devel Subject: Re: Why does adding a useless copy-sequence and discarding the result make my ELisp 40 times faster? Date: Sat, 25 Mar 2017 09:49:00 -0400 Message-ID: <96d5bde3-fc20-750e-abc7-541b2abd2bd8@gmail.com> References: <77900613-3b45-52f4-5770-38fe6f27e69c@gmail.com> <83vaqxbzub.fsf@gnu.org> <8760ixhc9a.fsf@luca> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1490449754 9154 195.159.176.226 (25 Mar 2017 13:49:14 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 25 Mar 2017 13:49:14 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 Cc: emacs-devel@gnu.org To: Andreas Politz , Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Mar 25 14:49:10 2017 Return-path: Envelope-to: ged-emacs-devel@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 1crm42-0001bF-UF for ged-emacs-devel@m.gmane.org; Sat, 25 Mar 2017 14:49:07 +0100 Original-Received: from localhost ([::1]:37425 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1crm49-0005X8-1u for ged-emacs-devel@m.gmane.org; Sat, 25 Mar 2017 09:49:13 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55490) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1crm42-0005X0-QZ for emacs-devel@gnu.org; Sat, 25 Mar 2017 09:49:07 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1crm3y-0006QL-Q3 for emacs-devel@gnu.org; Sat, 25 Mar 2017 09:49:06 -0400 Original-Received: from mail-qt0-x22f.google.com ([2607:f8b0:400d:c0d::22f]:33183) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1crm3y-0006QA-M8; Sat, 25 Mar 2017 09:49:02 -0400 Original-Received: by mail-qt0-x22f.google.com with SMTP id i34so10305294qtc.0; Sat, 25 Mar 2017 06:49:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:cc:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding; bh=8pyx1hjg25g2gTsvwYI6VcI3BDutdjkit6Q11R9IScM=; b=BsTQLh+rxYTwstW2OtGqh6QiOxOskTdrEOxuoE7ic8wh77aoyCmNZLDMwMdeqePGAn fxgr0XYr9nsYI25Bt0TttAraZcjWsoH5xu/T+lL+1lbhhpp25E6npXXHvPXTFFg9bCkv 0rdlC6R8lgDMp6SiB+Yn8ZIrJfN23cYsjCDyVtWwskLZ1x3YKa/biIgJ4CtgJvxTedSh qsp7XIbRMyQW2O6e6vpJCJzLoR2inXFChgEnt1VgS6KpwPYcfzJ3njnjmq5zQ+cOmbx3 U0G46ejj7vaxmG50VNPgDGfvj6fqtkALbF+KZINlfaEQdS4t5LblS/uDDDjNKt4n1eoz kprg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=8pyx1hjg25g2gTsvwYI6VcI3BDutdjkit6Q11R9IScM=; b=JJe1Rle/VlS0WefwqH5isIJEB56RDkDRxZ0em1MGQWIF/F7KsSzt0+Uk2hGyYZs3Mx n+KAT3sRMTBR55iRV6co8wrc//b3FyyhWOsW0Tvk0XC8n/g6hiRW4mgOhbnbWO90LkiW X2IUGNUbKSYFKD8D1xqjlwCsLbYzHQuXjR7TwUzVWYl6kxdqCGOeGGRgBWlaDpBVvpk7 6nVONQzhpGYB2Ugowr1/ayX4nl6DZBd77vpvSuGzW0U8sG94r8i8eK9X4s6M8wnJiXOU 63JkYT4KB1O+PC2QD86JWmXQQp+D1XZrxjZcj6oA2hKzFH5Y7HICP1te4lZLVCX1G/H/ /FNw== X-Gm-Message-State: AFeK/H3pI1OiZ1XnRF7z1+CnT6aaQnFwDLAwSbKC78vjN9GmhYFtZrwRu/qEBrKJswuy9w== X-Received: by 10.237.37.41 with SMTP id v38mr12809529qtc.24.1490449741981; Sat, 25 Mar 2017 06:49:01 -0700 (PDT) Original-Received: from [18.189.26.125] (dhcp-18-189-26-125.dyn.mit.edu. [18.189.26.125]) by smtp.gmail.com with ESMTPSA id s5sm3734956qkd.33.2017.03.25.06.49.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 25 Mar 2017 06:49:01 -0700 (PDT) In-Reply-To: <8760ixhc9a.fsf@luca> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2607:f8b0:400d:c0d::22f X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 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:213337 Archived-At: On 2017-03-25 06:38, Andreas Politz wrote: > The limiting factor may also be python itself... > > ;; python2 > ((0.114342188 0 0.0) > (0.715895279 0 0.0) > (2.120252213 0 0.0) > (1.02429565 0 0.0)) > > ;; bash = "while read;do : ;done" > ((2.008305836 0 0.0) > (1.999825023 0 0.0) > (2.026715753 0 0.0) > (2.060320318 0 0.0)) Interesting! But doesn't this just show that bash is uniformly slow? Do you see the same surprising timings with the read.c program that I sent, or with cat, as with Python? Clément.