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Re: [quicwg/base-drafts] clarify what happens when consuming CIDs excessively (#2428)

MikkelFJ <notifications@github.com> Wed, 06 February 2019 09:16 UTC

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Subject: Re: [quicwg/base-drafts] clarify what happens when consuming CIDs excessively (#2428)
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One low-level observation:

CID's need to be looked up in a hash table or similar. For a busy server multiplexing many connections, it want this table in fast cache, also to reject invalid CID's fast. You may be able to handle 5000 connections efficiently, but if you are required to handle 8x5000 this can degrade performance, especially on rejection. You can counter this by cryptographically mapping multiple CID's a single internal CID but that is not the simplest approach.

Therefore, choosing a minimum number of CID's should be done with care. Would 2 or 3 not be sufficient for most use cases?

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