[action] [PR:1774] [master] Smart Counter Poll to allow counters to work properly on Broadcom platforms.

[mssonicbld]

Summary

This is change is to address #1753 and the master implementation of the HLD added in sonic-net/SONiC#2190.

FlexCounter.cpp assumes all ports support the same counter capabilities. This causes issues on most Broadcom platform switches as there are different types of ports on a switch that does not support the same set of counters.

Fix by dynamically discovering what each interface is capable of during initialization of syncd.

For more detials please refer to the above issue and HLD.

Testing

Master testing is also done, but due to frequent changes in master tests fail on other issues depending which commit is used for testing. However, none of the issues seem related to this change.

More comprehensive testing is done on the 202511 stable branch:
Testing is done on both a Arista-7060X6-16PE-384C-B-O128S2 and Arista-7260CX3-D108C8 on 202511 with the tests:

sonic-mgmt/tests/dhcp_relay/test_dhcp_counter_stress.py
sonic-mgmt/tests/drop_packets/test_drop_counters.py
sonic-mgmt/tests/drop_packets/test_configurable_drop_counters.py
sonic-mgmt/tests/gnmi/test_gnmi_countersdb.py
sonic-mgmt/tests/snmp/test_snmp_queue_counters.py

A full sonic-mgmt test suite run has also been ran (202511). There are no notable fallout compared to sonic-mgmt runs without this change. This is ran on both XGS and DNX Broadcom platforms.

EDIT: Jul 13, 2026
202605 Testing
Additional 202605 testing has been done.
Comparing full 202605 sonic-mgmt test results on TH5 (using Arista-7060X6-64PE) with and without these changes, there is no difference in the test results.

Performance Impact:

All logic change is only done in the counter initialisation stage of FlexCounters.cpp - there is no polling logic change at all.
Therefore, any performance impact is limited to any new execution of syncd - i.e. reboot / config reload / systemctl restart.

Tested on several topologies:

This impact seems reasonable for what this offers.

The fastest operation that would cause a syncd restart is a systemctl restart swss, that is a operation that spans minutes. The worst real life scenario on a HwSKU with older CPU and many interfaces takes additional ~17 seconds. New, high interface-count HwSKUs only takes an extra ~2 seconds.

As for memory usage - the impact is on the order of kilobytes, the impact is negligible as the system has GBs of RAM.

Signed-off-by: Sonic Build Admin sonicbld@microsoft.com

[mssonicbld]

Original PR: #1774

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This cherry pick PR has been opened for more than 3 days. The mssonicbld will attempt to retry.

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/azpw retry

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Retrying failed(or canceled) jobs...

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Retrying failed(or canceled) stages in build 1166288:

✅Stage BuildTrixie:

• Job armhf: retried.