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Re: [quicwg/base-drafts] Length-prefixes and flow control (#1432)

Mike Bishop <notifications@github.com> Mon, 11 June 2018 22:23 UTC

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From: Mike Bishop <notifications@github.com>
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Subject: Re: [quicwg/base-drafts] Length-prefixes and flow control (#1432)
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The issue is cross-stream dependencies.  If you craft a very large message which requires data from another stream to process it, if the application sucks up the large message anyway, then it will explode its memory.  The point of flow control is to limit this, by constraining the *unprocessed* data at any time.  We're using unread as a stand-in for unprocessed, and the corollary is that you shouldn't read something you know you won't be able to process.  The guidance in HQ is to read far enough to decide whether you can process the message, and if not, stop reading until you can.

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