From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Petteri Hintsanen Newsgroups: gmane.emacs.help Subject: Re: [External] : Passing buffers to function in elisp Date: Mon, 27 Feb 2023 22:44:43 +0200 Message-ID: <87v8jmkfd0.fsf@iki.fi> References: <87mt56hg4e.fsf@iki.fi> <87bklihln8.fsf@iki.fi> <87pm9yf0ph.fsf@web.de> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="5993"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:b86rdqXoNOOzIDfjckpDamPapH8= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Mon Feb 27 21:45:31 2023 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1pWkNG-0001Po-Rl for geh-help-gnu-emacs@m.gmane-mx.org; Mon, 27 Feb 2023 21:45:30 +0100 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pWkMh-0000Nm-Am; Mon, 27 Feb 2023 15:44:55 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pWkMf-0000BR-9K for help-gnu-emacs@gnu.org; Mon, 27 Feb 2023 15:44:53 -0500 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pWkMd-0001pB-FX for help-gnu-emacs@gnu.org; Mon, 27 Feb 2023 15:44:52 -0500 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1pWkMb-0000eb-2G for help-gnu-emacs@gnu.org; Mon, 27 Feb 2023 21:44:49 +0100 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:142869 Archived-At: Stefan Monnier via Users list for the GNU Emacs text editor writes: >> If `emms-info-native--read-and-decode-ogg-page' is called very often >> (hundreds of times or more), it's probably better to use one single >> buffer instead of a fresh temp buffer every single time. I tried this and, for a moment, I _think_ it shaved off something like 20-25% of the memory usage (according to the memory profiler). That would be a big win. Sadly enough, it was just for a moment, because I cannot replicate it anymore. It wasn't a particularly controlled setup, so probably I just messed up something at some point. Nonetheless, using a persistent buffer seems to be the right thing to do, and seeing how many " *foo-bar-baz*" buffers there are, it even looks like a pattern. Also, if I interpreted profiler's hieroglyphs correctly, it told me that this setq (setq stream (vconcat stream (plist-get page :stream))) is a pig -- well, of course it is. I'm accumulating byte vector by copying its parts. Similarly bindat consumes a lot of memory. I think I can replace vectors with strings, which should, according to the elisp manual, "occupy one-fourth the space of a vector of the same elements." And I guess that accumulation would be best done with a buffer, not with strings or vectors. But bindat internals are beyond me. > That's definitely something to consider. Another is whether the ELisp > code was byte-compiled (if not, then all bets are off, the interpreter > itself generates a fair bit of garbage, especially if you use a lot of > macros). No, it was not byte-compiled. I don't know how many macros there are. Just by hand-waving I'd say "not that many". But again what bindat does is beyond me. I'll try byte-compiling after the code is in good enough shape to do controlled experiments. > Are you using `bindat-type`? No, not yet. I have been thinking about it, not only because the current implementation is riddled with ugly evals and kludges, but I want to save the kittens ;-D I also need to discuss with EMMS maintainer whether using Emacs 28+ feature is okay. Thanks to all for insights, I learned a lot. Petteri