From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: Re: Will we ever see a low latency/high performance PCM api for usb, firewire, avb ? Date: Fri, 26 Apr 2019 14:22:47 +0200 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from webclient5.webclient5.de (webclient5.webclient5.de [IPv6:2a01:4f8:212:88::2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 160B0F8961C for ; Fri, 26 Apr 2019 14:22:48 +0200 (CEST) Received: from [10.1.2.4] (unknown [94.101.37.79]) by webclient5.webclient5.de (Postfix) with ESMTPSA id 99251558355F for ; Fri, 26 Apr 2019 14:22:47 +0200 (CEST) In-Reply-To: Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Jaroslav Kysela wrote: > Any idea to improve the transfer method? The problem with the serial buses is > that you have to queue usually more samples to avoid underruns. When the ALSA buffer is not mmapped, it is possible to treat the contents of the packet buffers as the ring buffer, i.e., to write the sample data directly into the packets, ideally even after they have been queued. Regards, Clemens