[sflowmgrd] Infer sampling rate dynamically based on oper speed

[vivekrnv]

What I did

1. Remove sflowSpeedRateInitMap and infer the default sampling rate based on speed on the interface.
2. Make the rate inference based on oper_speed.

Why I did it

1. With Static Map, adding a new speed would require updating the code.
2. auotneg might change the operational speed on the port but the default sampling rate is not updated

How I verified it

1. UT's:

[----------] 11 tests from SflowMgrTest
[ RUN      ] SflowMgrTest.test_RateConfiguration
[       OK ] SflowMgrTest.test_RateConfiguration (0 ms)
[ RUN      ] SflowMgrTest.test_RateConfigurationCfgSpeed
[       OK ] SflowMgrTest.test_RateConfigurationCfgSpeed (0 ms)
[ RUN      ] SflowMgrTest.test_OnlyStateDbNotif
[       OK ] SflowMgrTest.test_OnlyStateDbNotif (0 ms)
[ RUN      ] SflowMgrTest.test_LocalRateConfiguration
[       OK ] SflowMgrTest.test_LocalRateConfiguration (0 ms)
[ RUN      ] SflowMgrTest.test_LocalRateConfWithOperSpeed
[       OK ] SflowMgrTest.test_LocalRateConfWithOperSpeed (1 ms)
[ RUN      ] SflowMgrTest.test_newSpeed
[       OK ] SflowMgrTest.test_newSpeed (0 ms)
[ RUN      ] SflowMgrTest.test_CfgSpeedAdminCfg
[       OK ] SflowMgrTest.test_CfgSpeedAdminCfg (0 ms)
[ RUN      ] SflowMgrTest.test_OperSpeedAdminCfg
[       OK ] SflowMgrTest.test_OperSpeedAdminCfg (0 ms)
[ RUN      ] SflowMgrTest.test_SflowCfgAfterPortCfg
[       OK ] SflowMgrTest.test_SflowCfgAfterPortCfg (0 ms)
[ RUN      ] SflowMgrTest.test_SflowCfgAfterOperSpeed
[       OK ] SflowMgrTest.test_SflowCfgAfterOperSpeed (1 ms)
[ RUN      ] SflowMgrTest.test_RateConfigEgressDir
[       OK ] SflowMgrTest.test_RateConfigEgressDir (0 ms)
[----------] 11 tests from SflowMgrTest (2 ms total)

2. Run manual tests on a DUT

Test normal speed change without autoneg

root@dut:/home/admin# show sflow interface | grep Ethernet220
| Ethernet220 | up            |          100000 |

root@dut:/home/admin# config interface speed Ethernet220 50000
root@dut:/home/admin# show sflow interface | grep Ethernet220
| Ethernet220 | up            |           50000 |

root@dut:/home/admin# config interface speed Ethernet220 25000
root@dut:/home/admin# show sflow interface | grep Ethernet220
| Ethernet220 | up            |           25000 |

Test rate change with autoneg

Ethernet205 <-> Ethernet209 Back to back connected

root@dut:/# show interfaces status 
Ethernet205              205      25G   9100    N/A   etp52b  routed      up       up    QSFP28 or later         N/A
Ethernet209              209      25G   9100    N/A   etp53b  routed      up       up    QSFP28 or later         N/A

<Check sampling rate before >
root@dut:/# show sflow interface
| Ethernet205 | up            |           25000 |
| Ethernet209 | up            |           25000 |

<Enable autoneg on 209>
root@dut:/# config interface autoneg Ethernet209 enabled
<Change speed on the peer port>
root@dut:/# config interface speed Ethernet205 10000

<Speed on 209 is updated because of autoneg>
root@dut:/# show interfaces status 
Ethernet205              205      10G   9100    N/A   etp52b  routed      up       up   QSFP28 or later         N/A
Ethernet209              209      10G   9100    N/A   etp53b  routed      up       up   QSFP28 or later         N/A

<sampling rate updated on both the ports>    
root@dut:/# show sflow interface
| Ethernet205 | up            |           10000 |
| Ethernet209 | up            |           10000 |

<disable autoneg> 
root@dut:/# config interface autoneg Ethernet209 disabled

root@dut:/# show sflow interface
| Ethernet205 | up            |           10000 |
| Ethernet209 | up            |           10000 |

[dgsudharsan]

@venkatmahalingam @prsunny Can you please help to review the changes?

[venkatmahalingam]

@Gokulnath-Raja Please take a look at the changes.

[Gokulnath-Raja]

Kindly test following,

1. With MAX interface and restart various container such as sflow, SWSS etc to see at all time sampling rate is programmed properly
2. Toggle to port oper status and ensure sampling rate is programmed properly

[Gokulnath-Raja]

Do we need to default as NA_SPEED instead of empty check??

[vivekrnv]

orchagent may write NA_SPEED to oper_speed in STATE_DB, setting it as empty will let us know if oper_speed field is written to state-db

[Gokulnath-Raja]

ok thanks for the clarification

[Gokulnath-Raja]

Check first oper_speed != NA_SPEED && m_sflowPortConfMap[alias].oper_speed != oper_speed

[vivekrnv]

!oper_speed.empty() check is required to understand if something is written to STATE_DB. (otherwise we'll have duplicate writes to APPL_DB). If the oper_speed happen to be NA findSamplingRate() has logic to check if the speed is NA and if so, written the sampling rate based on configured speed

[Gokulnath-Raja]

ok thanks for the clarification

[vivekrnv]

Kindly test following,

1. With MAX interface and restart various container such as sflow, SWSS etc to see at all time sampling rate is programmed properly
2. Toggle to port oper status and ensure sampling rate is programmed properly

Hi,

I've tested those scenarios and also ran sonic-mgmt tests to verify the functionality.

[dgsudharsan]

@Gokulnath-Raja Can you please re-review?

[skg-net]

@vivekrnv Can you please update the Quality Metric (Alpha/Beta/GA) for the feature either in this PR comments or in HLD itself based on https://github.com/sonic-net/SONiC/blob/master/doc/SONiC%20feature%20quality%20definition.md
Thanks