Git Issues: Reserved Stream-ID Bit

James M Snell <> Sat, 20 April 2013 19:44 UTC

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From: James M Snell <>
Date: Sat, 20 Apr 2013 12:43:06 -0700
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Subject: Git Issues: Reserved Stream-ID Bit
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The question is: "R: A reserved 1-bit field. The semantics of this bit
are not defined...What is the purpose for this field?...Why not just
have a 32-bit stream identifier?

Currently, the spec mandates that stream ID's originating from the
client must be odd, and stream ID's originating from the server must
be even. This makes for a much more restricted range of stream id's
and ensures that they'll be used up much faster. Personally, I'd
prefer that this extra reserved bit be used to indicate the
"directionality" of the stream. All streams originating from the
client would have this bit unset, all streams originating from the
server would have this bit set. This gives each side a total of
(2^32)-1 streams to work with. That ought to be more than enough.