220 34940 <60cbae8d-2a6d-4d1b-9fdf-5c4c913ee0a0@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: Mingxin Wang Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Idea about "std::pmr::memory_resource" Date: Sun, 15 Oct 2017 05:35:27 -0700 (PDT) Lines: 89 Approved: news@gmane.org Message-ID: <60cbae8d-2a6d-4d1b-9fdf-5c4c913ee0a0@isocpp.org> References: <0a8293b4-3246-47a5-9881-bc1ca4b91772@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_15811_892752831.1508070928060" X-Trace: blaine.gmane.org 1508070927 20157 195.159.176.226 (15 Oct 2017 12:35:27 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sun, 15 Oct 2017 12:35:27 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBDNMBNHJWIGBBEFMRXHQKGQE5ARVJLI@isocpp.org Sun Oct 15 14:35:23 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-vk0-f72.google.com ([209.85.213.72]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1e3i8Y-0004ah-Ik for gclcip-std-proposals@m.gmane.org; Sun, 15 Oct 2017 14:35:22 +0200 Original-Received: by mail-vk0-f72.google.com with SMTP id n70sf5029137vkf.8 for ; Sun, 15 Oct 2017 05:35:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isocpp-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:message-id:in-reply-to:references:subject:mime-version :x-original-sender:reply-to:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-subscribe:list-unsubscribe; bh=ClUTJcoMOp62O5f+bKYWLeq4Trl80rGuS1PfA5fb7eU=; b=ZjhGVdltbVSmM+RdMUh0y816wFbFqwfyQcQXAP1+w2tzEAJsQKe6ClJr97PyXNTsnl SZQi8B3MqKxveEzaw0hHxL3H0Eo8AM/OJahJwpfO3fwFTWhTOfDMcvWWZE7QqKLyZA01 73wkSehUKJTmTSbLkBp4V42LKxfJ+CpHHkV22F8Q+er22DN2Aj+RBsoJ9GKyBxtMpTz7 CezD39XHGGq1RapfX/2ZwKMbcywkXOtxz8Zh4t7yLRYPehHAxegavv0uSJKQNe9iC40l 8uGwkE8iBYWSYUiMDI83fHSTwsL5SHdBVpkMfQvGVpafqG1A13RbymhLQ6QwpyrFaezi b43g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:message-id:in-reply-to:references :subject:mime-version:x-original-sender:reply-to:precedence :mailing-list:list-id:x-spam-checked-in-group:list-post:list-help :list-archive:list-subscribe:list-unsubscribe; bh=ClUTJcoMOp62O5f+bKYWLeq4Trl80rGuS1PfA5fb7eU=; b=WXMnYai0RbS6JdPr0q5y3tMHXtQ/Vi4UIKQm5EtPVe2rHGLA/LkTg6zW9oppwbccaG hhMRRWntcGwohRs6tFEpRuzXNe5w33iw+2AIgHePVrqnjBm4b/mptvezpmN1xFMk0NSu asYY4TBoMoZbKg1iUq5yfv494IPwyNEEGtYh2kPjWpJ35WhHep77UtgkXnppd+8V8dSZ LJpAT2NzKq66/wsQSogNt59vaKLIOzHNRhLhUEFT2eCgkcoSEAcGOZhHIo5xrK5APXoT 3HepuHEwNrgr+1oRrKpmZCRRMJ0g44kOidZHAm/Fjt08Zj2AtmTRRdZ+J9F5CCyuJy+A hmDw== X-Gm-Message-State: AMCzsaX3ie8Elht5L6UOstmxP1OV+T9rwFqK+tOpZ5+2N3N8ePQZaEML Xi9brJCwNAcGvZCM0K6GyPwEUw== X-Google-Smtp-Source: AOwi7QDrXiIOTFO+1qlAlBPGhlOMxhU3WfNt6AfvdLMKYOHsxzN/QBydx65UUF7efCb637+yfUCzKQ== X-Received: by 10.176.81.249 with SMTP id h54mr3552070uaa.98.1508070929805; Sun, 15 Oct 2017 05:35:29 -0700 (PDT) X-BeenThere: std-proposals@isocpp.org Original-Received: by 10.159.45.140 with SMTP id v12ls1505497uaj.20.gmail; Sun, 15 Oct 2017 05:35:28 -0700 (PDT) X-Received: by 10.31.69.204 with SMTP id s195mr491731vka.12.1508070928532; Sun, 15 Oct 2017 05:35:28 -0700 (PDT) In-Reply-To: X-Original-Sender: wmx16835vv@163.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:34940 Archived-At: ------=_Part_15811_892752831.1508070928060 Content-Type: multipart/alternative; boundary="----=_Part_15812_610364458.1508070928060" ------=_Part_15812_610364458.1508070928060 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sunday, October 15, 2017 at 2:48:51 PM UTC+8, Jonathan M=C3=BCller wrote= : > > > > It is non-standard but my memory library provides an allocator concept=20 > similar to those you've described. You can find it here:=20 > github.com/foonathan/memory=20 > > . > > > I agree that making the PMRs polymorphic by default wasn't an ideal=20 > choice. They should have been template based and provide a type erasure= =20 > wrapper. > > However, I've heard that the virtual overhead doesn't really matter much. > Although the "virtual overhead" is acceptible in many cases, it is an=20 evidence that "PMRs" still has room to improve. --=20 You received this message because you are subscribed to the Google Groups "= ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp= ..org/d/msgid/std-proposals/60cbae8d-2a6d-4d1b-9fdf-5c4c913ee0a0%40isocpp.or= g. ------=_Part_15812_610364458.1508070928060 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Sunday, October 15, 2017 at 2:48:51 PM UTC+8, Jonathan = M=C3=BCller wrote:

<plug>
It is non-standard but my memory libra= ry provides an allocator concept similar to those you've described. You= can find it here: gi= thub.com/foonathan/memory.
</plug>

I agree that making the PMRs po= lymorphic by default wasn't an ideal choice. They should have been temp= late based and provide a type erasure wrapper.

<= /div>
However, I've heard that the virtual overhead do= esn't really matter much.

A= lthough the "virtual overhead" is acceptible in many cases, it is= an evidence that "PMRs" still has room to improve.

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To unsubscribe from this group and stop receiving emails from it, send an e= mail to std-proposa= ls+unsubscribe@isocpp.org.
To post to this group, send email to std-proposals@isocpp.org.
To view this discussion on the web visit https://groups.google.= com/a/isocpp.org/d/msgid/std-proposals/60cbae8d-2a6d-4d1b-9fdf-5c4c913ee0a0= %40isocpp.org.
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