From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id A849DA0543 for ; Thu, 7 Jul 2022 18:01:29 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 6389A406B4; Thu, 7 Jul 2022 18:01:29 +0200 (CEST) Received: from mail-oi1-f173.google.com (mail-oi1-f173.google.com [209.85.167.173]) by mails.dpdk.org (Postfix) with ESMTP id 98C91415D7 for ; Thu, 7 Jul 2022 18:01:28 +0200 (CEST) Received: by mail-oi1-f173.google.com with SMTP id w83so23933195oiw.1 for ; Thu, 07 Jul 2022 09:01:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:from:date:message-id:subject:to; bh=YCA18V7CEL0ZT+6+jMzs2it8fecAfodnuNW45AsrF7g=; b=gv3wxqtL/ADAyM+k0YRDqwSQz690ANeBChoIrLWBsonZ54C+/M4liUEu/YAWIG0hcR yjTIEavAMYvwaE3QZu67DLWPQI64qgAgCOzAyQtOHaoEQ456lxvHCTQ3x8zp/yDQNq/5 KAxLf9s++nYm951B6BKm8lEp/7gVMCOt1SXqyASiGa97wazVDaCmmoau0KYLKAMSxqC9 UTXwRvXag35D5xylc7W1+6O6n++zVnNks5DVMsc5oUrpO2ITjcujXqvsjRbdTtVfywiE A1WnjwMdm/fcKM6AAw/cY6ZeMtnmB3rl/g1tNcuklLC22f5t7azE3e1OCRtGvQx6Ucux IHyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=YCA18V7CEL0ZT+6+jMzs2it8fecAfodnuNW45AsrF7g=; b=PgBPekMLXUsCz6yostftX91QBF5VvDDu9cpJVQV/8ag7PkPCZf2MKFImpHTSwh8yaA EnFu9yhHCuJNCHoRIbrFWyngzIgKE1Ytj6ZuxhkXhO5VWTe+HB7wRoo+o9mASuhwpKF5 W0Pl2jaxoz2MlPKBXpiv3GUAhh10wFfhQGTQf35j3eGdc6HOaTrfwryGqcKym5cX24eH +il3RJ1q5xGHURIoyJ9xdut7lK6rSmysEbmrp0jC/KL1Ka1sAzPjH/NNBN3IJk2A0dY2 XPLpiOUwZEc25Vekp/qLPsOOvV5ocFNxoHJUnKIadcCWv/3cjb1ZzcAmTg5X76Vk1QAS 6/Pg== X-Gm-Message-State: AJIora89zXNj1/DB3zIMcIHTDr+iZO7w0DhrcoBdklTTrMcGhbf9Mm0M G8oJBvzd/XNoUPvE2fKhfn5XC9YYl52I8GL2Wd1wpqSookbUdw== X-Google-Smtp-Source: AGRyM1tyS2zZXU+56IKCCA6E42XJw9QQ13k9wwSMK9IwdUdsK88N0MWv/yAxrylByrngQLptSrRxGkJ/vwmhpy62lQg= X-Received: by 2002:a05:6808:1a1c:b0:335:6440:8119 with SMTP id bk28-20020a0568081a1c00b0033564408119mr2839075oib.59.1657209687801; Thu, 07 Jul 2022 09:01:27 -0700 (PDT) MIME-Version: 1.0 From: Antonio Di Bacco Date: Thu, 7 Jul 2022 18:01:17 +0200 Message-ID: Subject: xxx_DESCS_PER_LOOP workaround To: users@dpdk.org Content-Type: text/plain; charset="UTF-8" X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: users-bounces@dpdk.org I'm using the ice PMD driver and, luckily, before going mad, I discovered that an rte_eth_rx_burst with a burst size of 1 will never succeed even if packets have arrived on the network card. This is due to the fact that ICE_DESCS_PER_LOOP is set to 4 or 8 and then you need to use a burst size not lower than 4 or 8. Now, I have an application where a single packet (9000 bytes) has to be delivered through the network with the lowest possible latency. Is it possible to workaround this limitation by accepting the performance degradation? I read that there is a "runtime" option -a ,rx_low_latency=1 but I'm not sure if this will be a workaround.