Configuring Micro-Burst Detection - Cisco Nexus 9000 Series Configuration Manual

Micro-Burst Monitoring
• The following are guidelines for micro-burst duration on TOR switches that contain a Network Forwarding
• By default, the switch stores a maximum of 1000 burst records. The maximum number of records is
• Too many back to back burst records while traffic is being drained from queues might result in jitter.

Configuring Micro-Burst Detection

You can enable micro-burst detection for all interfaces on the device.
For more information about EPLD programming to upgrade the FPGA, see the Cisco Nexus 9000 Series
FPGA/EPLD Upgrade Release Notes.
Engine (NFE2):
Note Micro-burst duration is the duration of the burst that can be detected. For example, when
micro-burst monitoring is configured for 1 - 3 queues, micro-bursts that exceed 0.64
microseconds are detected. Increasing the number of queues that are configured for
micro-burst monitoring increases the duration of the burst that can be detected.
1 - 3 queues
8 queues with 10 ports each
10 queues with 132 ports each
configurable within a range of 200 - 2000 records.
◦ At least, 20 burst records are stored for each queue even when the maximum number of burst
records has been reached.
◦ When the maximum number of burst records has been reached, the oldest record is deleted to allow
the storage of a new record.
◦ You can use the hardware qos burst-detect max-records number-of-records command to configure
the maximum number of burst records to store.
◦ You can use the show hardware qos burst-detect max-records command to display the maximum
number of burst records that can be stored.
To avoid jitter, configure the fall-threshold to be less than the rise-threshold. As a best practice, configure
the fall-threshold to be approximately 20% of the rise-threshold value (bytes).
Cisco Nexus 9000 Series NX-OS Quality of Service Configuration Guide, Release 7.x

Configuring Micro-Burst Detection

0.64 microsecond duration
9.0 microsecond duration
140 microsecond (0.14 millisecond) duration
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