use a separate snapshot cache for EDS #6250
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Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #6250 +/- ##
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- Coverage 81.33% 81.19% -0.15%
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Files 133 133
Lines 15775 15803 +28
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Hits 12831 12831
- Misses 2650 2678 +28
Partials 294 294
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| log logrus.FieldLogger | ||
| resources map[envoy_resource_v3.Type]xdscache.ResourceCache | ||
| defaultCache envoy_cache_v3.SnapshotCache | ||
| edsCache envoy_cache_v3.SnapshotCache |
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I switched to a SnapshotCache here instead of a LinearCache for EDS. It turns out the LinearCache doesn't behave as desired for us on control plane restarts. If Envoy already has config for a given resource at a particular version, then on a control plane restart, the version number of the resource in the cache will be reset to 1 (or close to 1), therefore will not be sent to Envoy since Envoy already has a "later" version of the resource. It will only be sent once the resource changes. However, this means that any changes that happened during the time of the restart may be ignored for a period of time.
With a SnapshotCache, any time the cached version differs from the last version Envoy saw, the resource will be re-sent, which better fits our use case given that versions are not durable across control plane restarts.
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Running CI a couple more times, then will back out the change to the default xDS server for merge |
- Triggers only EDS updates when endpoints change - Does not trigger EDS updates when only non-endpoints change Signed-off-by: Steve Kriss <stephen.kriss@gmail.com>
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- Triggers only EDS updates when endpoints change - Does not trigger EDS updates when only non-endpoints change Updates projectcontour#2134. Signed-off-by: Steve Kriss <stephen.kriss@gmail.com>
Uses a separate go-control-plane snapshot
cache for EDS. This allows Endpoints updates
to be independent of other config updates,
minimizing the amount of unnecessary xDS
traffic that is generated. This is more consistent
with the legacy Contour xDS server's implementation.
Note, this PR sets the envoy/go-control-plane xDS server as the default for testing purposes, but that change will be reverted before merge.