user: avoid full metadata copy in ExtractFromGRPCRequest#9
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Use metadata.ValueFromIncomingContext to read only the x-scope-orgid key instead of metadata.FromIncomingContext which deep-copies the entire metadata map. FromIncomingContext copies every key-value pair in the metadata map on every call. With 10 metadata keys per request, this is 16 allocations and 1016 bytes per call. ValueFromIncomingContext only copies the single requested key's []string slice. Benchmark results (10 metadata keys): name old time/op new time/op delta ExtractFromGRPCRequest-48 1389ns ± 2% 135ns ± 1% -90.3% name old alloc/op new alloc/op delta ExtractFromGRPCRequest-48 1016B ± 0% 80B ± 0% -92.1% name old allocs/op new allocs/op delta ExtractFromGRPCRequest-48 16.0 ± 0% 3.0 ± 0% -81.2% Signed-off-by: Alan Protasio <approtas@amazon.com>
danielblando
approved these changes
May 8, 2026
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Use metadata.ValueFromIncomingContext to read only the x-scope-orgid key instead of metadata.FromIncomingContext which deep-copies the entire metadata map.
FromIncomingContext copies every key-value pair in the metadata map on every call. With 10 metadata keys per request, this is 16 allocations and 1016 bytes per call. ValueFromIncomingContext only copies the single requested key's []string slice.
Benchmark results (10 metadata keys):