From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <users-bounces@dpdk.org> Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 825464621D for <public@inbox.dpdk.org>; Thu, 13 Feb 2025 22:56:11 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 0AE0E402B9; Thu, 13 Feb 2025 22:56:11 +0100 (CET) Received: from mail-oo1-f48.google.com (mail-oo1-f48.google.com [209.85.161.48]) by mails.dpdk.org (Postfix) with ESMTP id F037540279 for <users@dpdk.org>; Thu, 13 Feb 2025 22:56:09 +0100 (CET) Received: by mail-oo1-f48.google.com with SMTP id 006d021491bc7-5fcb9f9ef3bso207648eaf.0 for <users@dpdk.org>; Thu, 13 Feb 2025 13:56:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1739483769; x=1740088569; darn=dpdk.org; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=QB8l2ms7r0J2vNYK1Xxu3CUe2HA0gAim+16BIDa1Bqs=; b=HoWxbe2yqTieMBNgrk8GxIskOOsebUbmKeyrau6Uw59L2orjPiY05N6M8Pu8Xg+NOR HxY9/lHI4xn/ytH6MQqp+v3+LlyCX6FCDe3AOT/tLBtISUDmFMDtXlkqHWlN/amY40BC yxG928eLBCTRwqULynmG5yD16OyUe1fOCRDcqlfJ24BpTxJn76d/CF/5FcXcjUiXV12i A3qA1IiB2xkJDWUPEdk2fKgVdwnyPMZ3v0T6Y95Bu8TgqXvxyXAEFh12/qIdGc3Jcuxs 7ETAuJLJttfJZDryp6P3G1CBuDnmfKq/NgdWa1+btfRAbvvnJRPUCHWb48qokKPfz0JG 4CBA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739483769; x=1740088569; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=QB8l2ms7r0J2vNYK1Xxu3CUe2HA0gAim+16BIDa1Bqs=; b=Jue6AQo5TEN8L9O69bM5sDM0t3qKgvKcWAKmeIsao3YagAXiuBCne1jdfSRegq8dNm 1Mj5kmUrIen6Dq0TvOgyGIcv/EXXOGBVRSLRXW71TqIdGV6Q3M/4UNdBl+WopohU/B8F ZbJyJ28nGTShTXisGQXPNlPRxfH7v16KLYcv85wVaN4pYmPZMsTCNNFdkxbDpF1QjrzK +1BrJYhIW4KflswrNnqQDzdyifTvWkpfHjNBJV3Nk0fV0aywZriwcDLJWtm3vRgxaNwJ b+VjfR94a0ByCDfoUQvMNLZB6mP0eoisgLynjtvzHlM8ot/jT90yC9/APtTWCdHrUocY qC/Q== X-Gm-Message-State: AOJu0YwKfz5lrNIsFKsogEnDaV4l71YukuRiJSbyqh5kXxN2rKlnkYdS E08nQbBFKhKMfS/gckHCLW9mx5xZ6CU9rHy4LgHkubH0anMh4EcsG2MQxSL2hATvT0wNB5TUY6V bbKLqp5iqoqug25SS7ZcXOuvL7lYZ0PKC X-Gm-Gg: ASbGncuOxuiWJjJUj+5Sn3M1qM6uMlCCiUuX3DqQRuMxL0q2AktJywkp4hw85E8DfEi qFVWcm6lMWOyHJaunrDuPvEAw/sSRubB+LWcWIoEvNKCmEA6LhIbH8rBudGTT4ei75nhxJ8Q= X-Google-Smtp-Source: AGHT+IFbmbrG0OMhwxeh8/nHfWLWJQKKJUh6odQ34coiR6oqDVv11t4QYia5ZBLXMR2+obkWRElTKXXuTM7YB1/A7RM= X-Received: by 2002:a05:6870:5490:b0:29f:b1d4:7710 with SMTP id 586e51a60fabf-2b8d67b8c03mr5431058fac.24.1739483768697; Thu, 13 Feb 2025 13:56:08 -0800 (PST) MIME-Version: 1.0 From: Alan Beadle <ab.beadle@gmail.com> Date: Thu, 13 Feb 2025 16:55:57 -0500 X-Gm-Features: AWEUYZmFrpKSQ58MHhQ8PhfoFShMEolxYikmcPFb_AF1WQCGFZTiPeQ52I6MSPo Message-ID: <CANTAOdzuSS0zdSW5L_+8obbaG-nh7nXy=qXFR3YsaxaxDA5YdA@mail.gmail.com> Subject: Questions about interrupts 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 <users.dpdk.org> List-Unsubscribe: <https://mails.dpdk.org/options/users>, <mailto:users-request@dpdk.org?subject=unsubscribe> List-Archive: <http://mails.dpdk.org/archives/users/> List-Post: <mailto:users@dpdk.org> List-Help: <mailto:users-request@dpdk.org?subject=help> List-Subscribe: <https://mails.dpdk.org/listinfo/users>, <mailto:users-request@dpdk.org?subject=subscribe> Errors-To: users-bounces@dpdk.org Hello, I am trying to use rte_epoll_wait() to avoid rx polling and reduce CPU utilization while preserving low latency. I am using the Intel X550-T2 NIC with DPDK 23.11 and the ixgbe driver. I was able to make interrupts work and my process is getting interrupts when a packet arrives. I followed the example here: https://stackoverflow.com/questions/69792978/using-interrupts-with-dpdk Before calling rte_epoll_wait(), I must first arm the interrupt by calling rte_eth_dev_rx_intr_enable() every time my thread is about to wait. However, if a packet arrives between these calls, the interrupt will not work and my process will only resume once the timeout is reached. This causes huge latency spikes unless my timeout is very short, and the minimum time of 1ms is still too long to tolerate this problem, since my goal is to keep latency low. Here are my questions: 1) Is there a way to prevent the thread from suspending at all if the interrupt is not "armed" anymore? 2) Is it possible to set a timeout shorter than 1 ms? It looks like this is not supported by rte_epoll_wait(). Thank you, -Alan Beadle