Reduce Allocations in ValidateSignature#2586
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When we need to create an enumerable with a single element in it, we are allocating a `new List<SecurityKey> { key }`. This allocates both the list, and then allocates a 4 element array backing the list (because this syntax is C# sugar for just calling Add on the collection).
Instead, use a collection expression which optimizes the single element case.
There was one method in Saml that had this pattern in it, but was unused. I opted to remove it. Please let me know if it should be preserved for some reason.
keegan-caruso
approved these changes
May 6, 2024
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See dotnet/roslyn#71147 for what Roslyn does in these cases. It generates a |
pmaytak
approved these changes
May 6, 2024
This was referenced Dec 2, 2025
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When we need to create an enumerable with a single element in it, we are allocating a
new List<SecurityKey> { key }. This allocates both the list, and then allocates a 4 element array backing the list (because this syntax is C# sugar for just calling Add on the collection).Instead, use a collection expression which optimizes the single element case.
There was one method in Saml that had this pattern in it, but was unused. I opted to remove it. Please let me know if it should be preserved for some reason.
Using an internal benchmark with 1,000 iterations, these allocations will be cut in half: