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Increase tolerance for 'ip-proto' hash_key on t2 topos #16188
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Increase tolerance for 'ip-proto' hash_key on t2 topos #16188
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'ip-proto' hash_key only has 8-bits of entropy which won't result in good distributions on systems with large ECMP groups
/azp run |
Azure Pipelines successfully started running 1 pipeline(s). |
@@ -41,6 +41,7 @@ class HashTest(BaseTest): | |||
# Class variables | |||
# --------------------------------------------------------------------- | |||
DEFAULT_BALANCING_RANGE = 0.25 | |||
RELAXED_BALANCING_RANGE = 0.80 |
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@arista-nwolfe - how did we arrive at this number?
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@tjchadaga I went through our results from the past 3 months and we were never higher than 0.80
on our T2 devices for ip-proto
.
/azpw run Azure.sonic-mgmt |
/AzurePipelines run Azure.sonic-mgmt |
Azure Pipelines successfully started running 1 pipeline(s). |
'ip-proto' hash_key only has 8-bits of entropy which won't result in good distributions on systems with large ECMP groups.
T2 systems have a 24-way ecmp which sees some paths deviate from the 25% threshold for the
ip-proto
hash key.This change increases the tolerance just for
ip-proto
andt2
full topologies.For more details see #16147
Summary:
Fixes #16147
Type of change
Back port request