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 97F0BA00C4 for ; Mon, 14 Feb 2022 09:49:23 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 2FFEF40C35; Mon, 14 Feb 2022 09:49:23 +0100 (CET) Received: from mail.deltatec.be (mail.deltatec.be [91.183.90.4]) by mails.dpdk.org (Postfix) with ESMTP id 66A8D4068C for ; Mon, 14 Feb 2022 09:49:21 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltacast.tv; s=AnsUTM; h=MIME-Version:Content-Type:Message-ID:Date:Subject :To:From:Sender:Reply-To:Cc:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=wAAedd6y8Z4aU0pYVoFCY4r2utMr6rRl9otVfTibcmg=; b=c0a+BxKpwOaEQfz1/ncEDlg/CQ OaPRlKHQ9whFAu/12l5mryOBbhrGQpch0DZwZ7do+jx1MR4GmDIrKHjTAvHBxWiA7kHdQOeGBh7hr m7U3OvFjgqmY2z+fXravIuFwz5YTAaCgpzNvw/eZ4SncIteWt6fyYKaLAVCIMppz3df8=; Received: from [172.16.4.5] (port=50767 helo=W2K19-SVR-5.office.deltatec.net) by mail.deltatec.be with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nJX2j-0007mz-1R for users@dpdk.org; Mon, 14 Feb 2022 09:49:09 +0100 Received: from W2K19-SVR-5.office.deltatec.net (172.16.4.5) by W2K19-SVR-5.office.deltatec.net (172.16.4.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.792.3; Mon, 14 Feb 2022 09:49:09 +0100 Received: from W2K19-SVR-5.office.deltatec.net ([::1]) by W2K19-SVR-5.office.deltatec.net ([::1]) with mapi id 15.02.0792.003; Mon, 14 Feb 2022 09:49:09 +0100 X-SASI-Hits: BODYTEXTH_SIZE_10000_LESS 0.000000, BODYTEXTH_SIZE_3000_MORE 0.000000, BODYTEXTP_SIZE_3000_LESS 0.000000, BODY_SIZE_10000_PLUS 0.000000, HTML_90_100 0.100000, NO_CTA_URI_FOUND 0.000000, NO_FUR_HEADER 0.000000, NO_URI_FOUND 0.000000, NO_URI_HTTPS 0.000000, OUTBOUND 0.000000, OUTBOUND_SOPHOS 0.000000, SENDER_NO_AUTH 0.000000, WEBMAIL_SOURCE 0.000000, WEBMAIL_XOIP 0.000000, WEBMAIL_X_IP_HDR 0.000000, __BODY_NO_MAILTO 0.000000, __BODY_TEXT_X4 0.000000, __COURIER_PHRASE 0.000000, __CT 0.000000, __CTYPE_HAS_BOUNDARY 0.000000, __CTYPE_MULTIPART 0.000000, __CTYPE_MULTIPART_ALT 0.000000, __DQ_NEG_HEUR 0.000000, __DQ_NEG_IP 0.000000, __FROM_DOMAIN_NOT_IN_BODY 0.000000, __FROM_NAME_NOT_IN_BODY 0.000000, __FUR_RDNS_SOPHOS 0.000000, __HAS_FROM 0.000000, __HAS_HTML 0.000000, __HAS_MSGID 0.000000, __HAS_XOIP 0.000000, __HTML_TAG_DIV 0.000000, __MIME_HTML 0.000000, __MIME_TEXT_H 0.000000, __MIME_TEXT_H1 0.000000, __MIME_TEXT_H2 0.000000, __MIME_TEXT_P 0.000000, __MIME_TEXT_P1 0.000000, __MIME_TEXT_P2 0.000000, __MIME_VERSION 0.000000, __MSGID_32HEX 0.000000, __OUTBOUND_SOPHOS_FUR 0.000000, __OUTBOUND_SOPHOS_FUR_IP 0.000000, __OUTBOUND_SOPHOS_FUR_RDNS 0.000000, __SANE_MSGID 0.000000, __STYLE_RATWARE_NEG 0.000000, __STYLE_TAG 0.000000, __SUBJ_ALPHA_END 0.000000, __TAG_EXISTS_HTML 0.000000, __TO_MALFORMED_2 0.000000, __TO_NAME 0.000000, __TO_NO_NAME 0.000000, __URI_NO_MAILTO 0.000000 X-SASI-Probability: 7% X-SASI-RCODE: 200 X-SASI-Version: Antispam-Engine: 4.1.4, AntispamData: 2022.2.14.81217 From: Antoine POLLENUS To: "users@dpdk.org" Subject: Understand main Lcore Thread-Topic: Understand main Lcore Thread-Index: AdghfPzrwtBdCX47QzahqUsdNk12Ow== Date: Mon, 14 Feb 2022 08:49:09 +0000 Message-ID: <50abd2e008604ec08ce7850281adf1c0@deltacast.tv> Accept-Language: en-US, fr-BE Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.16.6.199] Content-Type: multipart/alternative; boundary="_000_50abd2e008604ec08ce7850281adf1c0deltacasttv_" MIME-Version: 1.0 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 --_000_50abd2e008604ec08ce7850281adf1c0deltacasttv_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hello, We are struggling to understand how the main lcore works and what is exactl= y done in it when it run. This need of understanding come from some issues we see when setting the ma= in lcore on the core 0 NUMA 0. When we do that we see some latency spike in the packet interval time like = if the tx_burst was blocked for 1ms despite being on another lcore than the= main one. The spike are really annoying because our usecase is time sensitive. The questions are: - What is the exact role of the main lcore? - How does the main lcore works ? - Do you have recommendation on which cpu core to assign main lcore ? - Why would we observe the packet interval time only on core 0 ? - Is there an implication of having interrupt on the main lcore on the othe= r lcore ? Thank you in advance for your help, Antoine --_000_50abd2e008604ec08ce7850281adf1c0deltacasttv_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hello,
We are struggling to understand how the main lcore works and what is exactl= y done in it when it run.

This need of understanding come from some issues we see when setting the ma= in lcore on the core 0 NUMA 0.
When we do that we see some latency spike in the packet interval time like = if the tx_burst was blocked for 1ms despite being on another lcore than the= main one.

&nbs= p;

The spike= are really annoying because our usecase is time sensitive.

&nbs= p;

The quest= ions are:

- What is the exact role of the main lcore?

- How doe= s the main lcore works ?
- Do you have recommendation on which cpu core to assign main lcore ?<= /o:p>

- Why wou= ld we observe the packet interval time only on core 0 ?

- Is ther= e an implication of having interrupt on the main lcore on the other lcore ?=

Thank you in advance for your help,

Antoine

--_000_50abd2e008604ec08ce7850281adf1c0deltacasttv_--