Q-Logic 59042-07 A Manuel D’Utilisation
3 – Planning
Performance
59042-07 A
3-5
0
3.3.2
Bandwidth
Bandwidth is a measure of the volume of data that can be transmitted at a given
transmission rate. A port can transmit or receive at nominal rates of 1-Gbps or
2-Gbps depending on the device to which it is connected. This corresponds to
actual bandwidth values of 106 MB and 212 MB respectively. Two 1-Gbps source
ports can transmit to the same 2-Gbps destination port. Similarly, one 2-Gbps
source port can feed two 1-Gbps destination ports.
transmission rate. A port can transmit or receive at nominal rates of 1-Gbps or
2-Gbps depending on the device to which it is connected. This corresponds to
actual bandwidth values of 106 MB and 212 MB respectively. Two 1-Gbps source
ports can transmit to the same 2-Gbps destination port. Similarly, one 2-Gbps
source port can feed two 1-Gbps destination ports.
In multiple chassis fabrics, each link between chassis contributes 106 or 212 MB
of bandwidth between those chassis depending on the speed of the link. When
additional bandwidth is needed between devices, increase the number of links
between the connecting switches. The switch guarantees in-order-delivery with
any number of links between chassis.
of bandwidth between those chassis depending on the speed of the link. When
additional bandwidth is needed between devices, increase the number of links
between the connecting switches. The switch guarantees in-order-delivery with
any number of links between chassis.
3.3.3
Latency
Latency is a measure of how fast a frame travels from one port to another. The
factors that affect latency include transmission rate and the source/destination
port relationship. Port-to-port latency values on the switch are shown in
factors that affect latency include transmission rate and the source/destination
port relationship. Port-to-port latency values on the switch are shown in
.
Table 3-2. Port-to-Port Latency
Destination Rate
Source Rate
Gbps
1
2
1
< 1 µsec
< 1 µsec
1
1
Based on minimum sized frame of 36 bytes. Latency increases for larger frame sizes.
2
< 0.5 µsec
< 0.4 µsec