From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f41.google.com (mail-lf0-f41.google.com [209.85.215.41]) by dpdk.org (Postfix) with ESMTP id 0AA282C27 for ; Sun, 5 Feb 2017 11:38:28 +0100 (CET) Received: by mail-lf0-f41.google.com with SMTP id x1so31005070lff.0 for ; Sun, 05 Feb 2017 02:38:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=IJUXXoR7aQDu1AjK+uHcjteI+bmux321wT6vybSezME=; b=J8kLUbOFVQERWf2LB3awiG8aKJMM38IhFD7CMZAGHMo2S5qkGPYQsOP9Hwc5ObepTN hPS2qVK/QXlFAZXej+CoTiaamKbND/cMbwRRAR/YYAvqRKP2KRQ4J+o2+6WNKb+iZuV8 W9IY7bMCeJY1JbVU6ff/pdysMxqumgoODrFiL3CJurvpDd/Uz1x4sgBKOkpppKghERVn G6D8aFQZZmzq0keZbEOT5voA0lejdZJj16Vi/mEs9vuHdUMoXgSSkjbPrmCmL6Pa+a7N u08gNG2YKljzr18Qj+Sy9a0Lnbvf1AZwPYyow6+idtWNDu9yfXsnBXqGK6IlXjx8WYMx vGCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=IJUXXoR7aQDu1AjK+uHcjteI+bmux321wT6vybSezME=; b=eeYscvQvZHuPWBX7xiQ8btWErcfhQKX+av+m1syAT7s4pxgqgF1jBgT4cTpHC9BNQY 5TEqa05i6w5pmcpvQyYEByp/MuFj1gUk7aPJ+1io/0/0aJwmYzGw6lZmr+gC/FQkXz/n JTDkdcMjVd+SnhvCpnHjkphmqbimvNZXopw4FIDYiH7tjuUSJVSnxv1kEsnaiAFWZq9W C5buPwZICED9u0r1eZDpxziVyUaIa5s4GRWIAhnoZJfavdjbJkKGg+p2kPDSayX1sIVT hK2B5yLICWc5AUOc3JTivN2pce87nyLToJFSAMIOVadcGYn9irD/MGfXtt1gD7fjW0OP gHzA== X-Gm-Message-State: AMke39mcYUDKwBFVl8iBi7N6iGC7ZRKbvbCdnWgNjc834VwfR+rVTE/wIoHR7IOTFgZJ2mgFP+l5oK6am8W5CQ== X-Received: by 10.25.80.66 with SMTP id z2mr1616204lfj.157.1486291107378; Sun, 05 Feb 2017 02:38:27 -0800 (PST) MIME-Version: 1.0 Received: by 10.25.163.73 with HTTP; Sun, 5 Feb 2017 02:38:27 -0800 (PST) In-Reply-To: References: From: Gilles Roudiere Date: Sun, 5 Feb 2017 11:38:27 +0100 Message-ID: To: users@dpdk.org Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.15 Subject: Re: [dpdk-users] How to fix the number of RX desc to the highest value possible ? X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 05 Feb 2017 10:38:29 -0000 Hello, In my DPDK app, I would like to fix the number of RX descriptors to the maximum value available. As this is a trafic capture app (dpdkcap ), I do not want to loose any packet, so I want the buffers as big as possible. I have been trying to use the *dev_info.rx_desc_lim.nb_max* field, but it seems to produce memory allocation failures in some situation. (This value is obtained using* rte_eth_dev_info_get (portid, &dev_info) *, and used as the number of requested descriptors when calling* rte_eth_rx_queue_setup (...)*). One user is claiming having a message saying that the requested number of rx desc is not aligned to a power of 2, and that the requested value have been increased. In this situation I do understand why it does not work (the value goes over the max availabe), but I do not get why this value is not given aligned. Therefore, I wondered what the *dev_info.rx_desc_lim.nb_max *really mean: is that a maximum per queue ? Or the total number of allowed descriptors ? And what is the nb_align for ? The documentation is kind a incomplete about that. :/ So if any of you has more information about those values, I would really appreciate it. Thank you for your time, Regards, Gilles Roudiere