From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6065EC33CB6 for ; Thu, 16 Jan 2020 16:41:02 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D9E632073A for ; Thu, 16 Jan 2020 16:41:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="WecI+TSS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9E632073A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 1CBFB17BD; Thu, 16 Jan 2020 17:40:10 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 1CBFB17BD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1579192860; bh=xGmGCDwRi3zw+FLkM4K1M7gswC37lOnOr3eLvWQh92k=; h=To:References:From:Date:In-Reply-To:Cc:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=WecI+TSSvfHjPoXCBUyMQdKUtF7o4EX5gis8FsN15oZGgIs+8wcaK03ysUUiCbL0q c0HbTmKvg98zyXCqQDS0LKGdJ4ugF3JFZ+K0p53HIXQRCXsw1Mi0jw6TgLe0wdEZrE c+dhj65GfEyU+0z/EF2wdb0qVdic1m5AacM2Xqu8= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 55570F800E9; Thu, 16 Jan 2020 17:40:09 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id A4FB4F8014E; Thu, 16 Jan 2020 17:40:07 +0100 (CET) Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 308AFF800E9 for ; Thu, 16 Jan 2020 17:39:59 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 308AFF800E9 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Jan 2020 08:39:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,326,1574150400"; d="scan'208";a="274058700" Received: from frederic-mobl1.amr.corp.intel.com (HELO [10.251.150.187]) ([10.251.150.187]) by FMSMGA003.fm.intel.com with ESMTP; 16 Jan 2020 08:39:56 -0800 To: "Jie, Yang" , Takashi Iwai , Keyon Jie References: <20200116045318.5498-1-yang.jie@linux.intel.com> <97bbe88d1a6b63fe8e9b02bf0c5ce4a80553c48d.camel@linux.intel.com> <3c0a0067043d614cd4491b28acf6d49640746b15.camel@linux.intel.com> From: Pierre-Louis Bossart Message-ID: Date: Thu, 16 Jan 2020 10:39:56 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Cc: "alsa-devel@alsa-project.org" Subject: Re: [alsa-devel] [PATCH] ALSA: pcm: fix buffer_bytes max constrained by preallocated bytes issue X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" >> So, do you suggest not doing preallocation(or calling it with 0 size) for all >> driver with TYPE_SG? I am fine if this is the recommended method, I can try >> this on SOF I2S platform to see if it can work as we required for very large >> buffer size. Keyon, for the rest of us to follow this patch, would you mind clarifying what drives the need for a 'very large buffer size', and what order of magnitude this very large size would be. FWIW, we've measured consistently on different Windows/Linux platforms, maybe 10 years ago, that once you reach a buffer of 1s (384 kB) the benefits from increasing that buffer size further are marginal in terms of power consumption, and generate all kinds of issues with volume updates and deferred routing changes. Thanks -Pierre _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel