From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.ecotelecom.ru (mail.ecotelecom.ru [193.105.59.24]) by dpdk.org (Postfix) with ESMTP id 8E605AD7F for ; Tue, 7 Jun 2016 19:28:56 +0200 (CEST) Received: from [10.210.10.59] (unknown [10.210.1.240]) by mail.ecotelecom.ru (Postfix) with ESMTPA id 6944FD4023A for ; Tue, 7 Jun 2016 20:28:56 +0300 (MSK) From: Alexey Bogdanenko To: dev@dpdk.org Message-ID: <57570458.1080208@ecotelecom.ru> Date: Tue, 7 Jun 2016 20:28:56 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: [dpdk-dev] QoS grinder vs pipe wrr_tokens X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Jun 2016 17:28:56 -0000 Hello, I have a question regarding QoS grinder implementation, specifically, about the way queue WRR tokens are copied from pipe to grinder and back. First, rte_sched_grinder uses uint16_t and rte_sched_pipe uses uint8_t to represent wrr_tokens. Second, instead of just copying the tokens, we shift bits by RTE_SCHED_WRR_SHIFT. What does it accomplish? Can it lead to lower scheduler accuracy due to a round-off error? version: v16.04 Thanks, Alexey Bogdanenko