[quicwg/base-drafts] qpack: acking headers that do not reference the dynamic table is wasteful (#1603)

Dmitri Tikhonov <notifications@github.com> Wed, 25 July 2018 14:26 UTC

Date: Wed, 25 Jul 2018 07:26:43 -0700
From: Dmitri Tikhonov <notifications@github.com>
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Subject: [quicwg/base-drafts] qpack: acking headers that do not reference the dynamic table is wasteful (#1603)
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There is no need to acknowledge header blocks that do not reference the dynamic table.  These acknowledgements do not contain any information useful to the encoder.  I propose that the draft be modified to state that

```
    A header is acknowledged only when the Largest Reference in
    its Header Data Prefix is not zero.
```

This change
1. saves bytes -- improving compression and potentially avoiding extra unneeded _STREAM_ frames and packets; and
1. allows the encoder to drop state for such header blocks as soon as they are encoded.


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[quicwg/base-drafts] qpack: acking headers that d… Dmitri Tikhonov
Re: [quicwg/base-drafts] qpack: acking headers th… afrind
Re: [quicwg/base-drafts] qpack: acking headers th… afrind