http://kb.pert.geant.net/cgi-bin/twiki/view/PERTKB The PERTKB web of TWiki. TWiki is a Web-Based Collaboration Platform for the Corporate World. en-us Copyright 2010 by contributing authors TWiki Administrator [simon.leinen@switch.ch] The contributing authors of TWiki TWiki http://kb.pert.geant.net/PERTKB /twiki/pub/PERTKB/WebPreferences/edupert-small.gif http://kb.pert.geant.net/PERTKB/HostBus Bus architecture and performance Network (and other) interfaces attach to the motherboard using some kind of interconnect. Typically a motherboard has a couple of ... (last changed by SimonLeinen) 2010-09-01T22:01:50Z SimonLeinen http://kb.pert.geant.net/PERTKB/WireShark Wireshark Wireshark is a packet capture/analysis tool, similar to tcpdump but much more elaborate. It has a graphical user interface (GUI) which allows "drilling ... (last changed by SimonLeinen) 2010-08-25T15:39:41Z SimonLeinen http://kb.pert.geant.net/PERTKB/BsdOSSpecific OS Specific Configuration Hints: BSD Variants Performance tuning By default, earlier BSD versions use very modest buffer sizes and don't enable Window Scaling by ... (last changed by SimonLeinen) 2010-08-18T15:21:36Z SimonLeinen http://kb.pert.geant.net/PERTKB/SiFtr SIFTR Statistical Information for TCP Research Written by James Healy and Lawrence Stewart from Swinburne University in 2007, SIFTR is a kernel module for FreeBSD ... (last changed by SimonLeinen) 2010-08-18T15:15:31Z SimonLeinen http://kb.pert.geant.net/PERTKB/IPPerformanceMetrics IP Performance Metrics (IPPM) Working Group An IETF Working Group that has been chartered in 1997 to define metrics for network performance. Over the years, the group ... (last changed by SimonLeinen) 2010-08-18T13:14:44Z SimonLeinen http://kb.pert.geant.net/PERTKB/QuickStartTCP Quick Start TCP Quick Start TCP was codified in an Experimental RFC (RFC 4782) in 2007. Based on explicit feedback from the network, it can use a large Initial Window ... (last changed by SimonLeinen) 2010-08-18T13:14:09Z SimonLeinen http://kb.pert.geant.net/PERTKB/TcpHighSpeedVariants High Speed TCP Variants There have been numerous ideas for improving TCP over the years. Some of those ideas have been adopted by mainstream operations (after thorough ... (last changed by SimonLeinen) 2010-08-18T12:43:49Z SimonLeinen http://kb.pert.geant.net/PERTKB/GeneralTools Troubleshooting Procedures PERT Troubleshooting Procedures, as used in the earlier centralised PERT in GN2 (2004 2008), are laid down in GN2 Deliverable DS3.5.2 (see ... (last changed by SimonLeinen) 2010-08-17T11:42:31Z SimonLeinen http://kb.pert.geant.net/PERTKB/LargeSendOffloadLSO Large Send Offload (LSO) This feature is also known as "Segmentation Offload", "TCP Segmentation Offload (TSO)", " TCP Multidata Transmit (MDT), or "TCP Large Send ... (last changed by SimonLeinen) 2010-08-11T16:10:09Z SimonLeinen http://kb.pert.geant.net/PERTKB/MultiThreadDemux Network Adapters Demultiplexing to Multiple Threads Over the past years, multi threaded and multi core machines have become dominant, not just in the high performance ... (last changed by SimonLeinen) 2010-08-11T13:25:07Z SimonLeinen http://kb.pert.geant.net/PERTKB/AdaptersAndDrivers Network Adapter and Driver Issues One aspect that causes many performance problems is adapater and NIC compatability issues (full vs half duplex as an example. The ... (last changed by SimonLeinen) 2010-08-02T13:11:04Z SimonLeinen http://kb.pert.geant.net/PERTKB/LatestNews Latest News Efforts to increase TCP's initial congestion window The 78th IETF meeting is taking place in Maastricht this week, and one of the many topics being discussed ... (last changed by SimonLeinen) 2010-07-28T17:14:43Z SimonLeinen http://kb.pert.geant.net/PERTKB/TcpInitialWindow TCP's Initial Congestion Window (ICW or IW) The initial version of TCP Congestion Control specified that the congestion window should start at the maximum segment ... (last changed by SimonLeinen) 2010-07-28T16:46:37Z SimonLeinen http://kb.pert.geant.net/PERTKB/FlowControl TCP Flow Control Note: This topic describes the Reno enhancement of classical "Van Jacobson" or Tahoe congestion control. There have been many suggestions for improving ... (last changed by SimonLeinen) 2010-07-28T16:18:22Z SimonLeinen http://kb.pert.geant.net/PERTKB/SerializationDelay Serialization Delay (or Transmission Delay ) Serialization delay is the time it takes for a unit of data, such as a packet, to be serialized for transmission on a ... (last changed by SimonLeinen) 2010-06-17T06:29:13Z SimonLeinen http://kb.pert.geant.net/PERTKB/InterruptCoalescence Interrupt Coalescence (also called Interrupt Moderation , Interrupt Blanking , or Interrupt Throttling ) A common bottleneck for high speed data transfers is the ... (last changed by SimonLeinen) 2010-05-30T12:21:47Z SimonLeinen