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189
Tsi576 User Manual
June 6, 2016
Integrated Device Technology
www.idt.com
8. Performance
This chapter is a detailed description of the packet switching performance characteristics of the Tsi576.
It consists of the following general topics:
•
•
“Performance Monitoring” on page 190
•
“Configuring the Tsi576 for Performance Measurements” on page 194
•
“Port-to-Port Performance Characteristics” on page 195
•
“Multicast Performance” on page 197
•
“Congestion Detection and Management” on page 198
8.1
Overview
Performance for packet switching is characterized by three measurements: throughput, latency, and
latency variation.
Performance is specified for error free transmission and reception of packets. Performance is specified
for end-to-end transfers through the Tsi576. No performance specifications are made for the different
stages of transfers through the Tsi576.
Performance is specified for a single switch. Performance for larger systems can be computed from this
data.
8.1.1
Throughput
Throughput for packets is a measurement of the amount of packet data that can be transferred in a
given amount of time. It can be presented in different forms:
•
Percentage of a link’s bandwidth (for example, 56% of a 1x @ 3.125 Gbaud)
•
Number of packets of a given size per unit time (for example, 3000 44 byte packets every second)
•
Bit transfer rate (for example, 300 Mbits/s)
Throughput measurements include only successfully transferred packets. Measured throughput does
not include control symbols, retried packets, or other non-packet data transmitted/received on a link
(/K/ and /R/ characters).
8.1.2
Latency
Latency is the amount of time between packet reception and packet transmission. However, the specific
time at which packet reception and packet transmission are deemed to have started must still be
defined. Throughout this document, latency is measured as the time interval between the first bit of the
Start-of-Packet arriving at the ingress of the Tsi576 and that same bit leaving the device.
Содержание IDT Tsi576
Страница 1: ...IDT Tsi576 Serial RapidIO Switch User Manual June 6 2016 Titl...
Страница 20: ...About this Document 20 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...
Страница 34: ...1 Functional Overview JTAG Interface 34 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...
Страница 102: ...4 Internal Switching Fabric Packet Queuing 102 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...
Страница 230: ...11 Signals Pinlist and Ballmap 230 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...
Страница 506: ...B Clocking P_CLK Programming 506 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...
Страница 528: ...Index 528 Tsi576 User Manual June 6 2016 Integrated Device Technology www idt com...