a passive, no traffic condition. The EEE feature in switching platforms reduces overall energy
consumption, cooling, noise, and operating costs for energy and cooling. Lower power consumption
also means lower heat dissipation and increased system stability, less energy usage, thereby reducing
costs and impact on the environment.
EEE is a set of enhancements to the Ethernet specification to address power consumption during
periods of low data activity. EEE is specified in IEEE Std 802.3az-2010 which is an amendment to the
IEEE Std 802.3-2008 specification. The optional EEE capability combines the IEEE 802.3 Media
Access Control (MAC) sublayer with a family of physical layers defined to support operation in the Low
Power Idle (LPI) mode. When the LPI mode is enabled, systems on both sides of the link can save
power during periods of low link utilization. LPI signaling allows the LPI client to indicate to the PHY,
and to the link partner, that a break in the data stream is expected. The LPI client can then use this
information to enter power-saving modes that require additional time to resume normal operation. LPI
signaling also informs the LPI client when the link partner sends such an indication.
Port support for Energy Efficient Ethernet
• On ICX 7450 devices EEE is supported on 1G copper ports and 10G copper module ports.
• On ICX 7250 devices EEE is supported on 1G copper ports.
• You may notice port flap on the port when EEE is enabled.
• EEE is not supported on 1G fiber ports (ICX7450-48F), 4x10F module ports, and 1x40Q module
ports.
Enabling Energy Efficient Ethernet
Energy Efficient Ethernet (EEE) is supported on select Brocade devices and can be enabled globally or
per port.
Follow these steps to enable EEE globally or per port.
1. Enter global configuration mode.
2. Enter the
eee
command. The following example shows enabling EEE globally.
device(config)# eee
EEE Feature Enabled
3. To enable EEE at the interface level, enter the
eee
command in interface configuration mode.
device(config-if-e1000-1/1/1)# eee
EEE Feature Enabled on port 1/1/1
Histogram information overview
The histogram framework feature monitors and records system resource usage information. The main
objective of the histogram is to record resource allocation failures and task CPU usage information. The
histogram feature keeps track of task execution information, context switch history of tasks, buffer
allocation failure and memory allocation failure.
The histogram information is collected and maintained internally, in a cyclical buffer. It can be reviewed
to determine if resource allocation failures or task CPU usage may have contributed to an application
failure.
NOTE
Histogram information is not maintained across reboot.
Enabling Energy Efficient Ethernet
FastIron Ethernet Switch Administration Guide
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