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The test cam-usage command allows you to verify that there are enough available CAM entries before applying a policy-map
to an interface so that you avoid exceeding the QoS CAM space and partial configurations. This command measures the size of
the specified policy-map and compares it to the available CAM space in a partition for a specified port-pipe.
Test the policy-map size against the CAM space for a specific port-pipe or all port-pipes using these commands:
● test cam-usage service-policy input policy-map {linecard {0–2} } number port-set number
● test cam-usage service-policy input policy-map {linecard {0–2} } all
The output of this command, shown in the following example, displays:
● The estimated number of CAM entries the policy-map will consume.
● Whether or not the policy-map can be applied.
●
The number of interfaces in a port-pipe to which the policy-map can be applied.
Specifically:
● Available CAM — the available number of CAM entries in the specified CAM partition for the specified line card or linecard
port-pipe.
● Estimated CAM — the estimated number of CAM entries that the policy will consume when it is applied to an interface.
● Status — indicates whether the specified policy-map can be completely applied to an interface in the port-pipe.
○ Allowed — indicates that the policy-map can be applied because the estimated number of CAM entries is less or equal
to the available number of CAM entries. The number of interfaces in the port-pipe to which the policy-map can be
applied is given in parentheses.
○ Exception — indicates that the number of CAM entries required to write the policy-map to the CAM is greater than
the number of available CAM entries, and therefore the policy-map cannot be applied to an interface in the specified
port-pipe.
NOTE:
The show cam-usage command provides much of the same information as the test cam-usage command,
but whether a policy-map can be successfully applied to an interface cannot be determined without first measuring how
many CAM entries the policy-map would consume; the test cam-usage command is useful because it provides this
measurement.
● Verify that there are enough available CAM entries.
test cam-usage
DellEMC# test cam-usage service-policy input pmap_l2 linecard 0 port-set 0 linecard |
port pipe
Port-pipe | CAM Partition | Available CAM | Estimated CAM | Status
=====================================================================
0 L2ACL 500 200 Allowed(2)
SNMP Support for Buffer Statistics Tracking
SNMP support for buffer statistics tracking (BST) counters is implemented in the F10-FPSTATS MIB. BST counters allow you to
better monitor system resources and allocate buffer memory.
BST counters include the Max Use Count statistic, which provides the maximum counter value over a period of time.
In the F10-FPSTATS MIB, the following tables display BST counters:
● fpEgrQBuffSnapshotTable: Retrieves BST statistics from the egress port used in a buffer. This table displays a snapshot of
the buffer cells used by unicast and multicast data and control queues.
● fpIngPgBuffSnapshotTable: Retrieves BST statistics from the ingress port for the shared and headroom cells used in a
priority group. The snapshot of the ingress shared cells and the ingress headroom cells used for each priority group are
displayed in this table when PFC is enabled. This table is indexed by linecard index, port number and priority-group number.
● fpStatsPerPgTable: Retrieves information on the allocated Min cells, shared cells, and headroom cells for each priority group,
the mode in which the buffer cells are allocated (static or dynamic), and the used Min cells, shared cells, and headroom cells
for each priority group. The table returns a value of 0 if the allocation mode is static and a value of 1 if the allocation mode is
dynamic. This table is indexed by linecard number, port number and priority-group number.
Quality of Service (QoS)
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