Add sliceHeader for zero-copy parsing of message headers, use for client info
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server/client.go
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| index++ | ||
| } | ||
| return value | ||
| return hdr[start:index] |
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Should we also set cap here? That way if someone does try to do an append it will force a copy at that point?
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…lient info Signed-off-by: Neil Twigg <neil@nats.io>
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derekcollison
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Feb 4, 2025
| if v == nil { | ||
| return nil | ||
| } | ||
| return append(make([]byte, 0, len(v)), v...) |
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Maybe do allocation and copy? Unless we know append is as efficient for larger sizes..
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It's just as efficient when the capacity is preallocated, so just makes for a tidier one-liner.
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In the various places that we are handling client info from headers, like when queuing and pulling from the JS API queue or due to the service export, we could safely refer to the underlying header slice, instead of making a copy as
getHeader()does today.This PR adds a new
sliceHeader()that merely slices the input header instead, reducing copies considerably in any system where there is heavy usage of JS API requests.Signed-off-by: Neil Twigg neil@nats.io