Advanced Bottleneck Detection Settings - HP StoreFabric SN6500B Administrator's Manual

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Advanced bottleneck detection settings

Switch-wide alerting parameters:
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Alerts
Latency threshold for alert
Congestion threshold for alert - 0.700
Averaging time for alert
Quiet time for alert
Adjusting the frequency of bottleneck alerts
Depending on the circumstances, a problematic switch or port might be triggering alerts more
frequently than desired. The -qtime parameter can be used to throttle alerts by specifying the
minimum number of seconds between consecutive alerts. Thresholds are configured separately for
each type of bottleneck and statistical data are collected independently for each condition.
This parameter applies individually to each type of bottleneck detection; so there can be one
latency alert and one congestion alert in one quiet time.
Example of setting quiet time
This example sets a latency threshold of 0.8 for a time window of 30 seconds, and specifies that an
alert should be sent when 80% (0.8) of the one-second samples over any period of 30 seconds
were affected by latency bottleneck conditions; the system then waits 60 seconds before issuing
the next alert (assuming that there is one).
switch:admin> bottleneckmon --enable -lthresh 0.8 -time 30 -qtime 60
-alert=latency
switch:admin>
Notes
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Advanced bottleneck detection settings

Bottleneck detection uses the concept of an affected second when determining whether a
bottleneck exists on a port. Each second is marked as being affected or unaffected by a latency or
congestion bottleneck, based on certain criteria.
You can use the sub-second latency criterion parameters to refine the criterion for determining
whether a second is marked as affected by latency bottlenecks. For example, you might want to use
the sub-second latency criterion parameters in the following cases:
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Alert-related parameters can only be specified with --config when -alert is specified.
This is because -noalert is assumed if -alert is not specified, and -noalert cancels all
alert-related parameters. As long as you want alerts, you must include the exact form of alert
(-alert, -alert=congestion, or -alert=latency) in every --config operation, even if alerts are
already enabled.
The retention of settings applies only to the --config command, not to --enable.
An --enable operation behaves as if there is no preexisting user configuration, so if the --enable
command does not include -alert, but does specify alert-related parameters, that command
will fail.
You notice an under-performing application, but do not see any latency bottlenecks detected.
You can temporarily increase the sub-second sensitivity of latency bottleneck detection on the
specific F_Ports for this application.
- Yes
- 0.200
- 200 seconds
- 150 seconds
Fabric OS Administrator's Guide
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