Avoid initializing NIOSSLContext on every connection#84
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gjcairo merged 2 commits intoMay 27, 2026
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Motivation: In the secure upgrade pipeline, we currently initialize a [`NIOSSLContext`](https://github.com/apple/swift-nio-ssl/blob/8e3d34d5b6f1be4c1da71cd3f4b86c85f4da99b2/Sources/NIOSSL/SSLContext.swift#L288) on every connection. However, [constructing a `NIOSSLContext` is a very expensive operation](https://github.com/apple/swift-nio-ssl/blob/8e3d34d5b6f1be4c1da71cd3f4b86c85f4da99b2/Sources/NIOSSL/SSLContext.swift#L283-L285). We can easily avoid this by just initializing a `NIOSSLContext` once and using the same instance for all connections. Modifications: - Replaced the `makeServerConfiguration` helper extension on `NIOSSL.TLSConfiguration` to instead be in terms of `NIOSSLContext` (the new helper method is named `makeServerContext`). - Refactored the secure upgrade channel setup to use the new `makeServerContext` helper to initialize a `NIOSSLContext` just once, and plumb that through `setupSecureUpgradeServerChannels` -> `setupSecureUpgradeConnectionChildChannel` -> `makeSSLServerHandler`. - Updated associated test cases. Result: We now only create a new `NIOSSLContext` instance once upon server initialization rather than on every connection.
FranzBusch
approved these changes
May 27, 2026
gjcairo
approved these changes
May 27, 2026
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Motivation:
In the secure upgrade pipeline, we currently initialize a
NIOSSLContexton every connection. However, constructing aNIOSSLContextis a very expensive operation.We can easily avoid this by just initializing a
NIOSSLContextonce and using the same instance for all connections.Modifications:
makeServerConfigurationhelper extension onNIOSSL.TLSConfigurationto instead be in terms ofNIOSSLContext(the new helper method is namedmakeServerContext).makeServerContexthelper to initialize aNIOSSLContextjust once, and plumbed that throughsetupSecureUpgradeServerChannels->setupSecureUpgradeConnectionChildChannel->makeSSLServerHandler.Result:
We now only create a new
NIOSSLContextinstance once upon server initialization rather than on every connection.