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 904B4A0A0C; Fri, 2 Jul 2021 10:43:16 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 79D7B41365; Fri, 2 Jul 2021 10:43:16 +0200 (CEST) Received: from inbox.dpdk.org (inbox.dpdk.org [95.142.172.178]) by mails.dpdk.org (Postfix) with ESMTP id 8883640686 for ; Fri, 2 Jul 2021 10:43:15 +0200 (CEST) Received: by inbox.dpdk.org (Postfix, from userid 33) id 77849A0A0F; Fri, 2 Jul 2021 10:43:15 +0200 (CEST) From: bugzilla@dpdk.org To: dev@dpdk.org Date: Fri, 02 Jul 2021 08:43:15 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: DPDK X-Bugzilla-Component: ethdev X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: martin.weiser@allegro-packets.com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: Normal X-Bugzilla-Assigned-To: dev@dpdk.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter target_milestone Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.dpdk.org/ Auto-Submitted: auto-generated X-Auto-Response-Suppress: All MIME-Version: 1.0 Subject: [dpdk-dev] [Bug 749] mlx5: ConnectX-6 not all missed packets accounted for when using large maximum packet size X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" https://bugs.dpdk.org/show_bug.cgi?id=3D749 Bug ID: 749 Summary: mlx5: ConnectX-6 not all missed packets accounted for when using large maximum packet size Product: DPDK Version: unspecified Hardware: x86 OS: Linux Status: UNCONFIRMED Severity: normal Priority: Normal Component: ethdev Assignee: dev@dpdk.org Reporter: martin.weiser@allegro-packets.com Target Milestone: --- Version: 21.05 (which is not available in the Bugzilla version field) When testing with ConnectX-6 we recently became aware that a lot of missed packets did not show up in the statistics. After some further testing it looks like this is somehow related to using a large maximum packet size (which I believe makes the driver use a different scatter-gather receive path). The following testpmd invocations can be used to demonstrate this behavior. First an example for a "normal" run without the large maximum packet size: ./app/dpdk-testpmd -a c1:00.0 -a c1:00.1 -n 4 --legacy-mem -- --total-num-mbufs=3D2000000 --rx-offloads=3D0x2800 --mbuf-size=3D2331 --rxd= =3D4096 The xstats for one port look like this: rx_good_packets: 540138902 tx_good_packets: 537739805 rx_good_bytes: 298771912199 tx_good_bytes: 171950534158 rx_missed_errors: 572790 rx_errors: 0 tx_errors: 0 rx_mbuf_allocation_errors: 0 rx_q0_packets: 540138902 rx_q0_bytes: 298771912199 rx_q0_errors: 0 tx_q0_packets: 537739805 tx_q0_bytes: 171950534158 rx_wqe_errors: 0 rx_unicast_packets: 540711692 rx_unicast_bytes: 301254119575 tx_unicast_packets: 537739805 tx_unicast_bytes: 171950534158 rx_multicast_packets: 0 rx_multicast_bytes: 0 tx_multicast_packets: 0 tx_multicast_bytes: 0 rx_broadcast_packets: 0 rx_broadcast_bytes: 0 tx_broadcast_packets: 0 tx_broadcast_bytes: 0 tx_phy_packets: 537739805 rx_phy_packets: 540719221 rx_phy_crc_errors: 0 tx_phy_bytes: 174101493378 rx_phy_bytes: 301258662491 rx_phy_in_range_len_errors: 0 rx_phy_symbol_errors: 0 rx_phy_discard_packets: 7529 tx_phy_discard_packets: 0 tx_phy_errors: 0 rx_out_of_buffer: 0 tx_pp_missed_interrupt_errors: 0 tx_pp_rearm_queue_errors: 0 tx_pp_clock_queue_errors: 0 tx_pp_timestamp_past_errors: 0 tx_pp_timestamp_future_errors: 0 tx_pp_jitter: 0 tx_pp_wander: 0 tx_pp_sync_lost: 0 For this particular testcase the sum of rx_good_packets, rx_missed_errors a= nd rx_phy_discard_packets is always the expected total packet count of 540719221. If however testpmd is invoked like this: ./app/dpdk-testpmd -a c1:00.0 -a c1:00.1 -n 4 --legacy-mem -- --total-num-mbufs=3D2000000 --max-pkt-len=3D15360 --rx-offloads=3D0x2800 --mbuf-size=3D2331 --rxd=3D4096 The xstats after the testcase run look like this: rx_good_packets: 521670616 tx_good_packets: 522641593 rx_good_bytes: 288980135079 tx_good_bytes: 167591285708 rx_missed_errors: 879662 rx_errors: 0 tx_errors: 0 rx_mbuf_allocation_errors: 0 rx_q0_packets: 521670616 rx_q0_bytes: 288980135079 rx_q0_errors: 0 tx_q0_packets: 522641593 tx_q0_bytes: 167591285708 rx_wqe_errors: 0 rx_unicast_packets: 522550278 rx_unicast_bytes: 291559156800 tx_unicast_packets: 522641593 tx_unicast_bytes: 167591285708 rx_multicast_packets: 0 rx_multicast_bytes: 0 tx_multicast_packets: 0 tx_multicast_bytes: 0 rx_broadcast_packets: 0 rx_broadcast_bytes: 0 tx_broadcast_packets: 0 tx_broadcast_bytes: 0 tx_phy_packets: 522641593 rx_phy_packets: 540719221 rx_phy_crc_errors: 0 tx_phy_bytes: 169681852080 rx_phy_bytes: 301258662491 rx_phy_in_range_len_errors: 0 rx_phy_symbol_errors: 0 rx_phy_discard_packets: 30665 tx_phy_discard_packets: 0 tx_phy_errors: 0 rx_out_of_buffer: 0 tx_pp_missed_interrupt_errors: 0 tx_pp_rearm_queue_errors: 0 tx_pp_clock_queue_errors: 0 tx_pp_timestamp_past_errors: 0 tx_pp_timestamp_future_errors: 0 tx_pp_jitter: 0 tx_pp_wander: 0 tx_pp_sync_lost: 0 The rx_good_packets, rx_missed_errors and rx_phy_discard_packets counters n= ever sum up to the expected packet count: 521670616 + 879662 + 30665 =3D 522580943 540719221 - 522580943 =3D 18138278 (packets not accounted for) --=20 You are receiving this mail because: You are the assignee for the bug.=