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 3337142374 for ; Sun, 8 Jan 2023 22:06:10 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id E516140687; Sun, 8 Jan 2023 22:06:08 +0100 (CET) Received: from mail-yw1-f171.google.com (mail-yw1-f171.google.com [209.85.128.171]) by mails.dpdk.org (Postfix) with ESMTP id 49B494067C for ; Sun, 8 Jan 2023 22:06:07 +0100 (CET) Received: by mail-yw1-f171.google.com with SMTP id 00721157ae682-4a263c4ddbaso90812037b3.0 for ; Sun, 08 Jan 2023 13:06:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=RKX/cjJTFAjxkX6duUE3RKwH0JSCJW7gKqgpQze8Nl0=; b=Alf9wJhgcWfdqreTT5YqpAx+y/bTgsk1rh9xVGrgglRBs/H8KnV/5qSPrXiWdQh8BU le4/1nhKH/13OOtNHgoJVhmO72DCRfraNpDnPbFKYFqbz+c8PJyQUKU23c2kemuRZSnA b9Maz7g7Zcpse73gPqwZnPz/bCDVekImdTOhU2mRf+j1nvoJ20GG8rRrWjrrwJC4ahgc MVyxmTQakBQe1OQIN0pGpwLgXy0DPEd+NbNIMOTEE5koUqa+6IL0FfvrgK3UbbSw3ZAU /zKgU8x5mcgrG37pWg/S8CVVrxWXVLWiMJ4c1tI1N/hS5Pum1NlTXQcTBoLzTf/wL6rg l1sg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=RKX/cjJTFAjxkX6duUE3RKwH0JSCJW7gKqgpQze8Nl0=; b=cMbjPRV/WCepyAAF7jmHPXZEWQqRJC5MFmByRItf1Zht13b1MUQkDtaPrNBi5+oZ2Y sheHI1tMGYHFp4HOYe9d6dOHOzUok6WfPfemTxfzWU3EkHvwGLVi2AT6u2eX1GujGGu3 yd8DUkGLH9DmYiXJa9GlfyeOkhb73ZcnJajp1NintJ+Ec6WhkYn/FyP/ZOEwNXcLhaBS EGyGXhBVclakONSQNc9mGXYVchfcbxBPHbPqdc36AfO0Gj80E4yqFqicJoXZfFzcxlqC 9S+DwpRby06LivqiPKRCfL6SKH62nbTnFXdq16GK3jqNc4KEKHrEGziU+OiXV+5oSa99 9cog== X-Gm-Message-State: AFqh2kr/118vaVIEMMaVq8x0RATzA5Snex06FYcdBdgfTSC8Dy5hS0hd 9mx3Oz+pbWz4wKM2xZnwy50qvFn4QNJuFUfK99uS4BETG7I= X-Google-Smtp-Source: AMrXdXtV69DRyJDPn/9VfenNRulSPH5YAQYSFsgSUDtl6/GOJk47+Y5PEI6iDGDkIZ0urKRq3bhJwROABdA9++E1y/c= X-Received: by 2002:a81:8449:0:b0:44c:8b3:720b with SMTP id u70-20020a818449000000b0044c08b3720bmr1562444ywf.233.1673211966355; Sun, 08 Jan 2023 13:06:06 -0800 (PST) MIME-Version: 1.0 From: fwefew 4t4tg <7532yahoo@gmail.com> Date: Sun, 8 Jan 2023 16:05:55 -0500 Message-ID: Subject: DPDK and DMA To: users@dpdk.org Content-Type: multipart/alternative; boundary="000000000000e3801305f1c704fb" 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 --000000000000e3801305f1c704fb Content-Type: text/plain; charset="UTF-8" Consider a valid DPDK TXQ with its mempool of rte_mbufs. Application code will allocate a mbuf from the pool and prepare it with headers, data, and so on. When the mbuf(s) are enqueued to the NIC with rte_eth_tx_burst() does DPDK DMA the memory into the NIC? Is this an optimization worth considering? DPDK provides a DMA example here: http://doc.dpdk.org/api/examples_2dma_2dmafwd_8c-example.html Now, to be fair, ultimately whether or not DMA helps must be evidenced by a benchmark. Still, is there any serious reason to make mempools and its bufs DMA into and out of the NIC? Any perspective here is appreciated. --000000000000e3801305f1c704fb Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Consider a valid DPDK TXQ with its mempool of rte_mbufs. A= pplication code will allocate a mbuf from the pool and prepare it with head= ers, data, and so on.=C2=A0

When the mbuf(s) are enqueue= d to the NIC with rte_eth_tx_burst() does DPDK DMA the memory into the NIC?= Is this an optimization worth considering?=C2=A0

= DPDK provides a DMA example here:
http://doc.dpdk.org/api/examples_2dma_2= dmafwd_8c-example.html

Now, to be fair, ultimately whether or no= t DMA helps must be evidenced by a benchmark. Still, is there any serious r= eason to make mempools and its bufs=C2=A0DMA into and out of the NIC?
=

Any perspective here is appreciated.
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