Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262006AbVCATbP (ORCPT ); Tue, 1 Mar 2005 14:31:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262029AbVCATbP (ORCPT ); Tue, 1 Mar 2005 14:31:15 -0500 Received: from alog0342.analogic.com ([208.224.222.118]:50048 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S262006AbVCATak (ORCPT ); Tue, 1 Mar 2005 14:30:40 -0500 Date: Tue, 1 Mar 2005 14:29:24 -0500 (EST) From: linux-os Reply-To: linux-os@analogic.com To: Linux kernel Subject: Network speed Linux-2.6.10 Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4599 Lines: 117 Conditions: Intel NIC e100 device driver. Two identical machines. Private network, no other devices. Connected using a Netgear switch. Test data is the same thing sent from memory on one machine to a discard server on another, using TCP/IP SOCK_STREAM. If I set both machines to auto-negotiation OFF and half duplex, I get about 9 to 9.5 megabytes/second across the private wire network. If I set one machine to full duplex and the other to half-duplex I get 10 to 11 megabytes/second transfer across the network, regardless of direction. If I set both machines to auto-negotiation OFF and full duplex, I get 300 to 400 kilobytes/second regardless of the direction. I thought the problem must be the switch so I substituted a cross-over wire. The problem gets worse, maybe 50 to 100 kilobytes (random bursts) per second. `lspci` 00:00.0 Host bridge: Intel Corp. 82865G/PE/P DRAM Controller/Host-Hub Interface (rev 02) 00:01.0 PCI bridge: Intel Corp. 82865G/PE/P PCI to AGP Controller (rev 02) 00:1d.0 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI #1 (rev 02) 00:1d.1 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI #2 (rev 02) 00:1d.2 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI #3 (rev 02) 00:1d.3 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB UHCI #4 (rev 02) 00:1d.7 USB Controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) USB2 EHCI Controller (rev 02) 00:1e.0 PCI bridge: Intel Corp. 82801BA/CA/DB/EB/ER Hub interface to PCI Bridge (rev c2) 00:1f.0 ISA bridge: Intel Corp. 82801EB/ER (ICH5/ICH5R) LPC Bridge (rev 02) 00:1f.1 IDE interface: Intel Corp. 82801EB/ER (ICH5/ICH5R) Ultra ATA 100 Storage Controller (rev 02) 00:1f.2 IDE interface: Intel Corp. 82801EB (ICH5) Serial ATA 150 Storage Controller (rev 02) 00:1f.3 SMBus: Intel Corp. 82801EB/ER (ICH5/ICH5R) SMBus Controller (rev 02) 00:1f.5 Multimedia audio controller: Intel Corp. 82801EB/ER (ICH5/ICH5R) AC'97 Audio Controller (rev 02) 01:00.0 VGA compatible controller: nVidia Corporation NV17 [GeForce4 MX 440] (rev a3) 02:00.0 SCSI storage controller: Adaptec AHA-2940U/UW/D / AIC-7881U (rev 01) 02:01.0 Ethernet controller: 3Com Corporation 3c905B 100BaseTX [Cyclone] (rev 30) 02:04.0 Class 02b0: Analogic Corp: Unknown device 8004 (rev 07) 02:07.0 FireWire (IEEE 1394): Lucent Microelectronics FW323 (rev 61) 02:08.0 Ethernet controller: Intel Corp. 82562EZ 10/100 Ethernet Controller (rev 01) proc/interrupts CPU0 0: 507789786 IO-APIC-edge timer 1: 459692 IO-APIC-edge i8042 7: 0 IO-APIC-edge parport0 8: 1 IO-APIC-edge rtc 9: 0 IO-APIC-level acpi 12: 66 IO-APIC-edge i8042 14: 381384 IO-APIC-edge ide0 16: 0 IO-APIC-level uhci_hcd, uhci_hcd 17: 0 IO-APIC-level Intel ICH5 18: 0 IO-APIC-level libata, uhci_hcd 19: 0 IO-APIC-level uhci_hcd 20: 5748440 IO-APIC-level eth0 21: 278400 IO-APIC-level aic7xxx 23: 0 IO-APIC-level ehci_hcd NMI: 0 LOC: 507803974 ERR: 0 MIS: 0 These are identical machines/motherboards. Anybody have a clue why full-duplex sucks and mismatching FD/HD actually makes things faster? Is it possible that full-duplex is actually half-duplex of something strange like that? Ethtool statistics: NIC statistics: rx_packets: 1732112 tx_packets: 3612310 rx_bytes: 162571267 tx_bytes: 4119843621 rx_errors: 1094 tx_errors: 0 rx_dropped: 0 tx_dropped: 0 multicast: 0 collisions: 50986 rx_length_errors: 933 rx_over_errors: 0 rx_crc_errors: 84 rx_frame_errors: 77 rx_fifo_errors: 0 rx_missed_errors: 0 tx_aborted_errors: 0 tx_carrier_errors: 0 tx_fifo_errors: 0 tx_heartbeat_errors: 0 tx_window_errors: 0 tx_deferred: 298989 tx_single_collisions: 34534 tx_multi_collisions: 6779 tx_flow_control_pause: 122901 rx_flow_control_pause: 0 rx_flow_control_unsupported: 0 tx_tco_packets: 0 rx_tco_packets: 0 Cheers, Dick Johnson Penguin : Linux version 2.6.10 on an i686 machine (5537.79 BogoMips). Notice : All mail here is now cached for review by Dictator Bush. 98.36% of all statistics are fiction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/