From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: pjb@informatimago.com (Pascal J. Bourguignon) Newsgroups: gmane.emacs.help Subject: Re: Length of obarray vectors Date: Fri, 06 Nov 2009 13:03:59 +0100 Organization: Informatimago Message-ID: <87pr7vdfm8.fsf@galatea.local> References: <3da94a34-686a-4aaf-a627-109fdbc9150d@v25g2000yqk.googlegroups.com> <9760b6da-3458-4fd3-9e4e-febd18a5060a@b2g2000yqi.googlegroups.com> <87y6mjdht5.fsf@galatea.local> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1257511360 10285 80.91.229.12 (6 Nov 2009 12:42:40 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 6 Nov 2009 12:42:40 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Fri Nov 06 13:42:34 2009 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1N6O97-0006gr-Cy for geh-help-gnu-emacs@m.gmane.org; Fri, 06 Nov 2009 13:42:30 +0100 Original-Received: from localhost ([127.0.0.1]:56022 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1N6O96-0001Va-V2 for geh-help-gnu-emacs@m.gmane.org; Fri, 06 Nov 2009 07:42:28 -0500 Original-Path: news.stanford.edu!usenet.stanford.edu!news.glorb.com!news2.glorb.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail Original-Newsgroups: gnu.emacs.help Original-Lines: 27 Original-X-Trace: individual.net lcW6qxzLK27iKVG/tVVz7AAURISMkj4y/QrTD5re4ThKx/CZl1 Cancel-Lock: sha1:NjMzOWY4OTcyMzc3YmIxYWZlNGEyM2I4ZGYwMDg3YTIxZWI4ZWQzZA== sha1:1djIuDYuwUfNL06QteBr9FQyJoQ= Face: iVBORw0KGgoAAAANSUhEUgAAADAAAAAwAQMAAABtzGvEAAAABlBMVEUAAAD///+l2Z/dAAAA oElEQVR4nK3OsRHCMAwF0O8YQufUNIQRGIAja9CxSA55AxZgFO4coMgYrEDDQZWPIlNAjwq9 033pbOBPtbXuB6PKNBn5gZkhGa86Z4x2wE67O+06WxGD/HCOGR0deY3f9Ijwwt7rNGNf6Oac l/GuZTF1wFGKiYYHKSFAkjIo1b6sCYS1sVmFhhhahKQssRjRT90ITWUk6vvK3RsPGs+M1RuR mV+hO/VvFAAAAABJRU5ErkJggg== X-Accept-Language: fr, es, en X-Disabled: X-No-Archive: no User-Agent: Gnus/5.1008 (Gnus v5.10.8) Emacs/22.3 (darwin) Original-Xref: news.stanford.edu gnu.emacs.help:174469 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:69543 Archived-At: pjb@informatimago.com (Pascal J. Bourguignon) writes: > Nordlöw writes: > >> On Nov 6, 11:18 am, Nordlöw wrote: >>> What length should I use when I create a vector that will act as an >>> obarray? >>> My suggestion: The smallest prime larger than the number of symbols >>> that should be interned? >>> If this is correct why does (length obarray) give such a small number, >>> 15 >>> >>> Thanks, >>> Nordlöw >> >> It should be 1511, not 15. >> >> Forgot one thing: My guess: Is it a trade-off of performance (big >> length) and memory usage (small length)? > > The reason is that obarrays are not arrays, but trees. You're watching > only the root of the tree. Sorry, not trees, but kinds of hash-tables. -- __Pascal Bourguignon__