Fix data race and cache corruption in GetExternalMetric#1200
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rsgowman merged 2 commits intoMay 20, 2026
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Only applicable when `--external-metric-cache-ttl` is enabled. Previously, direct pointers to these objects were returned, which allows downstream handlers (e.g. transformResponseObject in k8s.io/apiserver) to mutate values in the cache, which can lead to a data race if two goroutines attempt to mutate it at the same time. This fix returns a deep-copy instead, which allows the caller to mutate their copy without impacting the cached copy. (Internal Google bug: http://b/511329740)
Which is a much better location for this fix. As suggested offline by laoj2@
laoj2
approved these changes
May 20, 2026
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Only applicable when
--external-metric-cache-ttlis enabled.Previously, direct pointers to these objects were returned, which allows downstream handlers (e.g. transformResponseObject in k8s.io/apiserver) to mutate values in the cache, which can lead to a data race if two goroutines attempt to mutate it at the same time.
This fix returns a deep-copy instead, which allows the caller to mutate their copy without impacting the cached copy.
(Internal Google bug: http://b/511329740)